094 - Experiments that changed fire science pt. 5 - Compartment fires at NBS with James Quintiere

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Hello, everybody.
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Welcome to Fire Science Show.
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If you follow last week's episode, you know exactly what's about to happen.
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I have interviewed professor James Quintiere on the us fire movement and the development of fire science in seventies and eighties in us and collaborations worldwide.
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It was quite fun.
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albeit the little, a bittersweet.
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With, uh, the politics involved and reasons why.
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The golden era of fire science has ended actually in there.
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Anyway today, we're coming back to these glorious times, but with a more technical approach.
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So I have interviewed James for another hour for about, uh, technicalities of research carried at NBS or NIST now.
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How this experiments were planned, how they choose the topics.
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Uh, who was involved, how they measured stuff, actually, that's, that's probably the most impressive part of it.
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How did they measure stuff?
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And while these guys were advanced in measuring stuff in fire, and so much more careful than many of fire researchers, I know myself, including, It's fascinating and inspiring to learn from James about that.
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I guess I'll be fine, ending intro as it is now, because I think I need to recommend listening to James Quintiere talking about some of the most impactful fire experiments ever conducted in history.
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So, yeah, let's spin the intro and jump i into the episodes.
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And now back to the experiments that changed fire science with James Quintiere.
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hello everybody.
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Welcome to Fire Science Show.
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I'm today again with Professor James Quintiere hello, James.
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Nice to have you here
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again.
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yes.
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Thank you.
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Thank you, Che.
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Really,
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really happy that you've, uh, to continue our interview.
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Last time, we were talking a lot about the history of the US Fire Movement, how many things were put into the place, the politics that did not help that much, and sometimes, uh, made destruction to the efforts of fire scientists.
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However, when we're discussing the mid seventies and your early days at there has been a lot of great fire science and experiments, and that's what I would like to cover in this part of the podcast.
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So, first, like, if you can, tell me, uh, what sorts of experiments were the ones that were most interesting for you happening in seventies, mid seventies, early
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eighties?
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Well, uh, I'm the kind of person that sees the big picture, so I would say almost all of them All of them.
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with, uh, uh, physics instead of chemistry.
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If it, dealt with flame retardants or maybe smoked particles or something like that.
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Hmm.
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didn't attract my attention as much as, flame spray and, the motion of, fluid in fire, pool fires, uh, fires in compartments.
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so all of that kind of attracted.
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and I think I spread my career over working in bits and pieces of territory.
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Well, uh, I struggle to call them bits and pieces because in your scientific curriculum, there is so many fundamental, papers and, and stuff that's absolutely fundamental to our modern understanding of fire.
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Calling them bits, uh, is maybe, uh,
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Well, enabled me and en and encouraged me to write a book to put that together and to try to, uh, create the book in terms of the bits and pieces, but to make it unified in a way.
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So the style of my book is more like a book on heat transfer or fluid mechanics, which tried to integrate the subject so that.
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Flame spread is not distinct from a fire plume There's things that are in common and it's becomes part of the same discipline of fire behavior.
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And so fire behavior, I think was the key attract to, to me, and fires and buildings and, uh, the most of the research at that time, either at NIST or in the academic field, and I would say most of it was in the academic field, focused in that territory.
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So they were looking at ignition flame spread, how things burn, what's the real science ingredients of a test method.
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Fires in compartments.
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Um, what happens when a flame hits a wall, when it hits a ceiling?
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why are laminate flames different than turbulent flames?
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So all of that came into a perspective for people to work on because nist assembled three groups in fire into one, Mm-hmm.
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and they brought in the research activity of the National Science Foundation, which was academia.
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Hmm.
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all of that came together and it came together under, the fire directorship of John Lyons.
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and people started thinking about all those bits and pieces.
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there were bits and pieces and the integration of them, was not considered.
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It was just, let's look at each individual piece.
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And when you look at pieces, what people do first is Let's burn something let's try to figure out what's going on.
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and so that was the really, the approach that people made those, uh, 1970s
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And, and I assume then you suddenly realize this, all these things intertwined together, one leads to another.
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You cannot consider flashover without understanding the, ignition of, of a solid
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surface, right?
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yes.
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I mean, you need to understand buoyancy.
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You need to understand heat transfer, flute mechanics, and then you, you need to understand how combustion comes into play in that.
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and one person we haven't mentioned is Brian Spalding.
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Brian Spalding in his early work, tried to look at combustion problems, in an engineering framework.
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In his later years, he moved to C F D because he felt that there was limitations, rightly so.
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you know, you've probably heard of the B number and the formulation of how things burn in terms of number Hmm.
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Schwab, Zeldovitch, in how you can make the equations of mass and heat transfer, assemble into one.
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And so that foundation was there from Spalding and Zel that allowed fire scientists to tap into.
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So that was an analytical tool that they could use.
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But really to look at this for the first time that many people were just stepping into it, they, they had to figure out what to look at, how to look at it.
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Uh, I could remember early scientists making measurements of temperature or velocity, and they were incorrect because they didn't understand that a thermocouple could have errors or that you were measuring velocity so low that, know, their instrument wasn't capable.
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there were a lot of challenges like, like that.
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and, bringing all of that together at N B S a catalyst.
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you've mentioned analytical tools that existed, What was the state of computational fire science at that point?
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Was it already the times where Howard Emmons had this first, code produced?
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No,
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No.
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no.
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The Howard Emmonds code grew out of the work, the early work in the seventies, in which, like even Howard Emmonds himself, he, he would have students, he had one student before all of this came together.
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Look at how Wood Cribs Mm-hmm.
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and expanded the work of Dan Gross Robertson from NBS and brought a theory into play.
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Emmons had John de Ris work on on Flame.
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and get, almost an exact solution for flame spread.
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Emmons worked uh, a fire whirl which was a phenomena not understood.
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Emmons had, Frank Tamanini work on, um, extinguishment of, fires.
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and then at the same time at FM was work going on on pool fires, uh, Modac.
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So people were focused on all of this.
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And there was an collaboration of the work between FM and Harvard.
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That program was linked.
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It was funded in as a link from NBS it wasn't funded to Harvard and to fm.
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It was funded.
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To Harvard and FM as a single entity.
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And because they had all these pieces, they decided they should put it together in a compartment fire.
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Okay, they, had a whole series of compartment fires with the best instrumentation unravel what was going on in the different pieces.
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And that led to Emmons, concept of a zone model.
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fantastic.
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And, and what was the understanding of the smoke dynamics at that point?
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The, the fire plumes, entrainment the
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layers.
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first of all, I think the smoke layer and the idea that you would have such a stratified Hmm atmosphere was something that was a revelation had to be probed.
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hmm.
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but because there was this focus on fire, many people recognized it.
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So Tanaka in Japan recognized it, and he could make his own model.
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Uh, people at, Illinois Institute of Technology, they got a grant from the National Science Foundation, and they could conceive of this, Emmons could conceive of it.
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I, I could do my little experiments in a compartment start to see this, Hmm.
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so I could form the basis of a system model that said, you have an upper layer, you have a lower layer, and you have flow through an opening.
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Let's conceive of the model in those terms, and now let's proceed to figure out how you get the flow in and out.
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what is the fire plume doing and build from there.
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And so this idea of a zone model came in several places because of the dynamic and interaction I think of the work.
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if you look the zones, the, i I think the distinguishment between the, the hot smoke zone and, and the free zone, you can observe that, you know, but wh when did you realize that the assumption that the, the hot zone can be considered as something, uh, unified, like, uh, How did you probe that?
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How did you
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validate that?
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well, in the work with Steckler, used aspirated thermocouple probes, which were first used I think at fm.
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Mm-hmm.
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to try to eliminate radiation effects.
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At the same time, work was going on, at, Caltech, under Ed Zukowski, and he would measure very carefully that temperature profile, in, uh, a room fire.
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And he would measure the gas profile and he would show, uh, how uniform, Hmm.
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was.
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of course, if you have a large room, like a corridor, like room, then it's going to vary as you move away from the fire.
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as a first approximation, the, that's what you have.
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And in that sense, Howard Emms was the last thing he was trying to work on was how to extend a room to a corridor like, enclosure.
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So you could allow for the, in the zone model, the variation in temperature longitudinally along the corridor.
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So there was, there was work trying to extend that, but there's really no need to do that when you realize that Tanaka applied his zone model to the World Trade Center after the bombing.
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And he modeled the smoke movement in the entire World Trade Center Hmm, with his own, with his own model.
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and Tanaka has built in wind effects.
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He's built in mixing effects between the layers that Ed Zukowski illuminated really.
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research.
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so the zone model concept came out of that, catalyst of interaction.
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and people watching, you know, like you said, you could see it, And so, it's like from an engineering point of view, Hey, let's model this as one zone and another zone.
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And they interact, they interact through the plume and they interact, through mixing.
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And they also interact because, when the lower wall gets hot, heat goes, the hot gases move up along that wall, Hmm.
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and then they encounter a hotter layer.
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So now they can't penetrate and they blur out the zone between the hot and cold layer.
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And there was research going on on that.
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So those things could be embedded into a zone model as secondary.
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Phenomenal.
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just like plume model is, is is also embedded as
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embedded.
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but of course when you embedded, you don't have the effect of coming in from one side knocking the plume mm-hmm.
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in the zone model, the plume stands up straight.
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But in a CF D model, the plume will bend over because it will, yield to that fluid of mechanics.
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and might do the mixing too, but it might not because that's a viscous, turbulent effect.
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So when designing experiments, to see inside the layers, what kind of tools you had available?
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You said, aspirating, thermal, uh, couples.
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That's, that, that I guess is quite advanced.
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Uh, what, what was your options for, for example, measuring heat fluxes?
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You, you had water called gouges at
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that point.
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Y Yes.
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there were these companies like Mether, Hmm whose founder actually had a PhD from who developed, thermopile type heat flux sensors.
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There's also a gourdon guide type hmm.
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a guard type heat flex sensor is a, a thin piece of metal in which you measure the center and the edge.
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And that difference corresponds to the heat flux that's received.
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thermo pile actually acts like a, it is a thin layer, but it has, the ability to measure temperature difference across that thin layer and from the conduction through it.
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uh, you can get the heat flux and the thermo pile one is far superior.
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The guard on gauge has some, uh, problems with it.
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So, people would use these and there would be issues of, Jorge, it's water cooled.
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You're putting it in a wall that's hot.
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Now you have a flow coming along and it sees this cold thing, and then suddenly it sees a hot thing again.
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And so there's issues of heat transfer, fluid mechanics of how to really interpret that gauge.
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mm-hmm.
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People were struggling with that.
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I think people forgot that today,
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And, uh, devices like we used today, like plate thermometers or thin skin color meters.
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They, they were not available.
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thermometer is Thermo couple.
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Yeah.
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type gauge.
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not the guard on gauge.
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It's actually measuring it.
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It's, you know, Wickstrom, promoted this thing.
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but it, it's been there for a long time and it can give you, uh, results.
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and so I, I've used that on occasion too.
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but to me, I think the, the, uh, thermo pile gauge is probably the best.
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The issues with those gauges is that need to make sure you know, the emissivity of the surface and the surface doesn't get cor fouled up during your experiment.
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In addition, if you try to separate out radiation, you put a window over it Mm-hmm.
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and the window is now transparent, but not completely to radiation.
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So you have that issue.
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you try to blow air over the window to keep soot from coming in, but it deposits anyway.
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So there are still issues with those, gauges.
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very fundamental issue that I don't think has been resolved, and maybe ISOs tried to do this, but I don't think they succeeded, to figure out how, how to find a way to calibrate these gauges.
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we, we still think about that, you know,
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You think about it and you don't have a way to do it.
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And when I was at NIST there are ways to do it.
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There's, there's improved techniques.
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There's a, device called a ellipsoidal, radiometer that has uh, gold surfaces in an ellipse.
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And you one focal point of the ellipse where the.
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the stuff enters and the other fo focal point, you have a sensor.
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Hmm.
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and the gold allows you to capture everything that comes in, uh, between the two focal points and you blow air through this thing.
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So you're always, blowing the smoke away.
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So you will always get the radiation that comes in.
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And that's an expensive, tool.
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If you go to Med Tham these days, the current guy that's operating that, he, he also has a PhD from M I t and I think he has a good understanding of these gauges.
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don't tell you how they calibrate them, but they probably have a black body someplace.
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And in my days at NIST in the seventies, I went to the people who did.
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radiometry measurements for light and things like that at mbs.
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So they were very accomplished and understood, uh, spectral aspects and emmis civilities, and they calibrated, uh, thermo pile gauge for me that I bought for mether, and they calibrated it up to, I think, I don't know, maybe two, kilowatts per meter squared.
00:20:00.840 --> 00:20:15.881
They couldn't go beyond, they couldn't go beyond the certain, so they, they, they calibrated two of these for me, and then I inherited a, a light source that gave me ability to get to a hundred kilowatts per meter squared.
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And so as, as long as I had a paint on this sensor, That was an emmis of one, Mm-hmm.
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did, I I, there was a special paint that gave you an emissivity of like 0.98.
00:20:28.173 --> 00:20:28.784
Mm-hmm.
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I had these two things calibrated, and although they were calibrated at a low heat flux, we could show that the thermo pile gauge works in a linear way.
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Interesting.
00:20:39.728 --> 00:20:40.048
Yeah.
00:20:40.208 --> 00:20:48.137
So if, if you go to higher heat flux, it's linear here, and you, you could show that, scientifically, uh, from the theory of that gauge.
00:20:48.550 --> 00:20:53.493
so we developed, this technique and it stays at NIST to this day.
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However, after I left nist, they lost one of the sensors and, they used the sensor.
00:21:00.678 --> 00:21:05.432
To give to anyone in the cone that wants to calibrate their cone.
00:21:05.647 --> 00:21:12.181
And so this sensor that is supposed to be in a lockbox is distributed to people to use.
00:21:12.682 --> 00:21:18.903
Now, when you, when you have a calibration source, you've developed transfer standards.
00:21:19.458 --> 00:21:21.087
So people haven't done that.
00:21:21.433 --> 00:21:26.653
the FAA, I've done work here, uh, I'm in New Jersey right now.
00:21:27.104 --> 00:21:44.594
they went to med and they got assurances that they would get the right so in recent years, I took the sensor I had, which came from nist, you know, traceable to NIST and That was traceable to mem.
00:21:45.574 --> 00:21:47.013
they were within 5%.
00:21:47.943 --> 00:21:51.814
So that's the kind of confidence level I have today in those sensors.
00:21:52.814 --> 00:21:56.653
I do think that a lot of people should pay attention to how they calibrate them.
00:21:56.917 --> 00:21:58.107
uh, that's astonishing.
00:21:58.107 --> 00:22:03.691
Like, uh, it, it seems you may even, like, you definitely had a higher comprehension of,
00:22:03.861 --> 00:22:07.993
of this, well, we worried about stuff like that in those days.
00:22:07.993 --> 00:22:12.114
Like Bernie McCaffrey wondered what's the best way to measure
00:22:12.743 --> 00:22:14.521
that, that was my next question, like,
00:22:14.594 --> 00:22:23.718
he, he said I could do it with a Pitot tube I know a pitot tube is, now it, if he did it with a hot wire and put it in a fire plume, Mm-hmm.
00:22:23.857 --> 00:22:25.008
it may not survive.
00:22:25.428 --> 00:22:26.038
Mm-hmm.
00:22:26.048 --> 00:22:33.395
the error that you would get from the so collection or the buoyancy effect on, on the thing There would be problems.
00:22:33.608 --> 00:22:46.470
So went to the pitot tube, but then later on he went to the bidirectional probe, particularly if we looked at doorway flows, because Heskestad developed that.
00:22:46.470 --> 00:22:52.950
And if he wanted to measure a doorway flow, didn't want to take a, have two pito tubes there.
00:22:53.211 --> 00:22:53.701
Yeah.
00:22:53.875 --> 00:23:01.803
made the bidirectional probe, which works on the same principle as the Pito tube, in place of two pito tubes in different directions,
00:23:02.182 --> 00:23:04.796
So, so to give a better context to listeners.
00:23:04.796 --> 00:23:07.955
So we are here talking about compartment fire dynamics.
00:23:07.955 --> 00:23:10.155
We just said that you had two layers.
00:23:10.155 --> 00:23:13.036
We've discussed how temperatures were measured in layers.
00:23:13.296 --> 00:23:19.675
The second, next most important thing is the opening at which the exchange of mass between the compartment and exterior happens.
00:23:20.006 --> 00:23:28.912
So you really need to very precisely quantify the flow in and flow out in both in terms of temperatures and terms of, the volumetric, uh, flows.
00:23:29.182 --> 00:23:31.893
So, so that's a challenging measurement even today.
00:23:31.893 --> 00:23:37.519
And I think, what you are now describing the bidirectional probe is still the, the standard, uh,
00:23:37.880 --> 00:23:38.000
approach.
00:23:38.480 --> 00:23:49.715
it is a way to do it, but at that time period, Hmm, like Bernie McCaffrey said, okay, uh, Heskes that developed this, h how does it work compared to the pido tube?
00:23:50.195 --> 00:23:50.346
hmm.
00:23:50.346 --> 00:23:55.339
what, uh, coefficient do I need for this bidirectional probe?
00:23:56.222 --> 00:24:03.363
how is it affected by the angle of the flow the direction of the velocity if it doesn't hit it straight on?
00:24:03.730 --> 00:24:17.150
And so people were concerned about that because if you put this thing in a doorway flow, you see right away that if flow is coming out, the flow goes down over the soften and then goes back up again.
00:24:18.369 --> 00:24:25.589
you, you have that probe now in a way where the flow is actually changing direction very strongly.
00:24:26.289 --> 00:24:29.779
And so is it measuring the, the flow accurately then?
00:24:30.000 --> 00:24:40.093
And so we looked at all those issues know, and Ed Zukowski was another guy that took pains to make sure he had the right measurements.
00:24:40.460 --> 00:24:48.730
and so measurement techniques were important and their validity, based on how they're calibrated or how, how they should be interpreted?
00:24:49.025 --> 00:24:52.755
were the experiments on the ceiling jets also carried at NIST at that time?
00:24:52.830 --> 00:24:54.901
Oh, the ceiling jet was done.
00:24:55.134 --> 00:25:04.134
it was probably motivated by John gave Ron Alper, uh, his, of baptism into fire by working on the ceiling jet.
00:25:04.691 --> 00:25:09.931
and so Ron, cobbled together, an analysis of a plume to the jet.
00:25:10.397 --> 00:25:14.065
And, there's been, you know, uh, work on it since.
00:25:14.805 --> 00:25:19.335
But, even Spalding said to me one time, he says, the jet will re Lamin rice.
00:25:20.154 --> 00:25:25.075
and so these are still issues that people haven't fully looked, looked at.
00:25:26.045 --> 00:25:41.698
one thing from the ceiling jet work that Ron Albert did is very useful for fire investigators or fire And that is that a kind of a useful, simple rule that comes out of the ceiling.
00:25:41.698 --> 00:25:45.417
Jet is the ceiling jet takes up 10% of the room height.
00:25:45.990 --> 00:25:52.974
So if you don't have a sprinkler or a detector in that region, they're the ceiling of 10%.
00:25:53.375 --> 00:25:54.564
It's not going to work.
00:25:55.028 --> 00:25:55.492
Yeah.
00:25:55.768 --> 00:25:59.012
very useful stuff came out of Ron Oh.
00:25:59.438 --> 00:26:06.417
But if you go to extend that and try to extend it to flame length under a ceiling, there's still work that needs to be done.
00:26:06.923 --> 00:26:08.083
and that work stopped?
00:26:08.496 --> 00:26:09.942
how about entrainment?
00:26:10.640 --> 00:26:16.240
McCaffrey did experiments on, on fire plumes within an immense amount of different fire plumes.
00:26:16.240 --> 00:26:19.079
How, how was, how was entrainment captured
00:26:19.369 --> 00:26:25.400
by you when in from McCaffrey measurements, he measured the distribution in a plume.
00:26:25.670 --> 00:26:26.339
of velocity?
00:26:26.569 --> 00:26:31.450
he, he measured the velocity across the radius Okay.
00:26:31.569 --> 00:26:32.210
different heights.
00:26:33.210 --> 00:26:43.266
if he, if he did that, he got the temperature and velocity over that radius, then he could integrate that and get mass Mm-hmm.
00:26:43.715 --> 00:26:54.529
However, at the edges, he had big, hes so, he did not put a lot of faith in his entrainment interpretation from those measurements.
00:26:54.759 --> 00:26:58.960
Don't tell me that my whole career is on that, on this equation.
00:26:59.134 --> 00:27:09.530
The entrainment work, the good entrainment work comes from Ed Zukowski and Byler picked it up as a, another student with Emmons.
00:27:10.371 --> 00:27:14.625
Ed Zokowski conceived of this thing that if you have a hood Mm-hmm.
00:27:14.671 --> 00:27:25.184
and you're extracting gases from it, and you put a fire plume below it, the fire plume will go and fill the hood and some will spill over.
00:27:25.460 --> 00:27:26.069
Mm-hmm.
00:27:26.266 --> 00:27:26.756
. Okay.
00:27:26.830 --> 00:27:38.500
Uh, but if you contain that fire plume in the hood and you don't get any spillover, essentially the, the plume is going into that layer.
00:27:38.915 --> 00:27:41.135
And the flow is coming out the top.
00:27:41.796 --> 00:27:53.903
And so if you vary the height of the, the flame, you could get entrainment at different levels in the flame by that, ture type, technique.
00:27:54.435 --> 00:28:01.432
and so Zukowski that showed that, that could be an accurate way of making the measurement.
00:28:01.685 --> 00:28:04.905
And then Byler and other people probably picked it up.
00:28:04.952 --> 00:28:08.563
But the best measurements come from, Zukowski.
00:28:08.807 --> 00:28:09.590
Fantastic.
00:28:09.776 --> 00:28:13.296
I think in zukowski did it at different sizes.
00:28:13.675 --> 00:28:14.175
All right.
00:28:14.500 --> 00:28:17.724
some people do it for a point source, Mm-hmm.
00:28:18.289 --> 00:28:20.130
can't work for a point source.
00:28:20.130 --> 00:28:28.002
You have to, get some measurements and then extrapolate it to a virtual origin and do things like that.
00:28:28.423 --> 00:28:32.762
But Zukowski measurements of different sizes.
00:28:33.289 --> 00:28:42.202
And again, if you try to take in the effective size, you can get an equation that covers most of the data.
00:28:42.816 --> 00:28:44.920
And I think it's in my book someplace.
00:28:45.009 --> 00:28:48.839
We, one of my students helped, integrate all of that data.
00:28:49.715 --> 00:28:54.670
but, there still needs to be work done there because, you have a big pool fire.
00:28:55.710 --> 00:28:56.480
A big pool.
00:28:56.480 --> 00:28:59.160
Fire is basically laminar at the base.
00:28:59.980 --> 00:29:05.460
So its entrainment is totally different than after you get beyond that region.
00:29:06.400 --> 00:29:14.586
Now is, if FDS is, giving you the answer to all of that, is it good in that lamina range as well as in the turbulent range?
00:29:14.935 --> 00:29:15.506
I don't know.
00:29:16.250 --> 00:29:16.371
Hmm.
00:29:16.465 --> 00:29:27.736
So those problems still are out there And because you people use C f D, think they got it all already when, they may not.
00:29:28.042 --> 00:29:28.765
That's the.
00:29:28.859 --> 00:29:35.492
before CF d you, you would focus on the experiment and you say, look, what's happening down there at the bottom?
00:29:35.492 --> 00:29:39.813
That's laminar, but I'm analyzing this as a turbulent plume.
00:29:40.259 --> 00:29:43.519
How can my my answer be right down at the bottom?
00:29:43.913 --> 00:29:45.695
and so that's, swept away.
00:29:45.695 --> 00:29:45.976
Now,
00:29:46.272 --> 00:29:47.123
Very, very
00:29:47.363 --> 00:29:47.643
interesting.
00:29:47.782 --> 00:29:53.022
You CF d prevents us from looking there because we say, look, we, we got it down there.
00:29:53.192 --> 00:29:54.222
It looks laminate.
00:29:54.789 --> 00:29:59.650
the lack of, um, of full scale research, uh, is, is
00:29:59.759 --> 00:30:00.319
full scale.
00:30:00.319 --> 00:30:02.319
You could do work on a, okay.
00:30:02.440 --> 00:30:06.836
spread on a napkin and, and still not fully understand it
00:30:06.952 --> 00:30:08.258
That's, a challenging,
00:30:08.258 --> 00:30:08.736
well.
00:30:08.736 --> 00:30:11.563
Well, I mean, you go to the work of flame spread, right?
00:30:11.952 --> 00:30:12.015
hmm.
00:30:12.015 --> 00:30:18.373
Concurrent flame spread is still complicated because it involves turbulent and radiation from that.
00:30:18.865 --> 00:30:27.625
but a post flow flame spread is more simple because it's a very kind of stable laminate flame moving, moving along.
00:30:28.615 --> 00:30:43.903
Fernandez when you, hopefully you'll interview him and he could give you the history of that and how they, they had to include, oxygen effects and velocity effects at the leading edge, in terms of a Damkohler number.
00:30:43.972 --> 00:30:44.583
Mm-hmm.
00:30:44.663 --> 00:30:49.049
And, and, and so w work like that was going on, but then it stopped.
00:30:49.461 --> 00:30:50.222
We got safety.
00:30:50.232 --> 00:30:51.143
We got everything
00:30:51.143 --> 00:30:51.326
now.
00:30:51.506 --> 00:30:57.460
I, I don't know, but you know, upward flame spread is still, upward burning.
00:30:57.710 --> 00:30:58.319
Mm-hmm.
00:30:58.500 --> 00:31:00.420
people I saw that did upward burning.
00:31:00.920 --> 00:31:21.567
To match experiments done at FM Global and by Jerry Faith are the using the, fire foam code from, uh, FM Global, uh, uh, Ning Ren and, ye I mean they produce good results, but they had to get that turbulent boundary layer working, Hmm.
00:31:21.613 --> 00:31:25.153
and I'm still not sure how NIST handles that.
00:31:25.744 --> 00:31:33.125
Now to go back to the experimental design, I think at some point of the interview you've, uh, you've referred to them as box buildings.
00:31:33.255 --> 00:31:36.837
Uh, so, uh, how you constructing them.
00:31:36.837 --> 00:31:46.357
How are you choosing like the configurations to, to go where you're starting with a very simple configuration of a compartment corridor mixing them.
00:31:46.387 --> 00:31:48.157
What was the logic behind that?
00:31:48.223 --> 00:31:52.336
Well, it, again, these things were motivated by c certain things.
00:31:52.772 --> 00:32:02.153
when I got my feet wet in fire nist, it was looking at these corridor fires involving floor covering Mm-hmm.
00:32:02.182 --> 00:32:02.903
a room in the
00:32:03.623 --> 00:32:07.365
you said that was an effect of a fire that happened and, and, blocked people.
00:32:07.736 --> 00:32:11.786
Yes, there was a fire in a, nursing home in Pennsylvania.
00:32:12.605 --> 00:32:22.220
And source of funding at that time was, the housing department in the US government, and they gave a lot of money to NIST to study those fires.
00:32:22.519 --> 00:32:30.712
So where one side of, uh, NIST and FIRE had money, directly through nist, which would be almost full funding.
00:32:31.452 --> 00:32:36.353
The other side of the NFI program needed to rely on projects like that.
00:32:36.952 --> 00:32:42.833
And they were able to get some really big, long-term projects, to look at, things like that.
00:32:42.843 --> 00:32:45.472
So both sides motivated each other.
00:32:45.773 --> 00:32:52.472
You know, you could see these big fires going on and other people are saying, oh, wow, I never saw that before.
00:32:52.627 --> 00:32:53.238
Mm-hmm.
00:32:53.542 --> 00:32:59.000
So we, we were in a learning mode, And we had a lot of stimulation.
00:32:59.691 --> 00:33:08.221
when, um, looking at, uh, that research, correct me if I'm wrong, but I I've, I didn't see any research on vehicle fires.
00:33:08.221 --> 00:33:08.461
I
00:33:09.361 --> 00:33:10.050
what kind
00:33:10.111 --> 00:33:13.008
vehicle fires Like cars in garage.
00:33:13.678 --> 00:33:14.167
Yeah.
00:33:14.242 --> 00:33:14.701
Uh, yes.
00:33:14.701 --> 00:33:20.788
There weren't yes, because at that time the focus was flashover fire tests.
00:33:20.968 --> 00:33:24.468
How are they doing a good job with materials?
00:33:25.468 --> 00:33:26.708
they causing flashover?
00:33:27.198 --> 00:33:28.983
So the, focus was room fires.
00:33:29.067 --> 00:33:40.662
the, fires in cars only became like, an anecdote when they discovered that the statistics on people dying in car fires, was, off by a factor of 10.
00:33:41.154 --> 00:33:48.884
And so immediately the, Death rate in fire in the US went from 8,000, a year, to 4,000
00:33:48.998 --> 00:33:51.468
by correcting By by, by correcting the, the vehicle.
00:33:51.468 --> 00:33:51.883
Okay.
00:33:52.258 --> 00:33:52.678
Yes.
00:33:52.938 --> 00:33:57.748
And, fires in motor vehicle to give you perspective is 40,000 Mm-hmm.
00:33:57.981 --> 00:34:03.654
and today the, I think the number might be 4,000 for fire in the US today.
00:34:04.347 --> 00:34:06.612
So no one worries about fire anymore.
00:34:06.679 --> 00:34:10.373
Well, I, I think now with the electric vehicles, it became a trendy topic again,
00:34:10.588 --> 00:34:17.135
Well, yes, but they'll solve that problem because look, using gasoline in vehicles for over
00:34:17.960 --> 00:34:19.639
which is kind of flammable
00:34:20.114 --> 00:34:20.534
Yes.
00:34:20.534 --> 00:34:24.414
More worse than the batteries always.
00:34:24.699 --> 00:34:25.693
They're flammable.
00:34:25.952 --> 00:34:35.992
The batteries are only going to be a problem if they're, they have a fatal flaw Hmm when they were made or if there's an accident.
00:34:36.202 --> 00:34:43.612
And the reason is, if you have one go bad, they'll all go bad because the batteries only this big.
00:34:44.105 --> 00:34:47.099
it's like a a, double A battery Yeah.
00:34:47.210 --> 00:34:49.550
has thousands of these things in their cars.
00:34:50.000 --> 00:34:50.420
And.
00:34:50.480 --> 00:34:53.800
so so they'll figure out a way to prevent it.
00:34:53.956 --> 00:35:02.396
Y your research, this era of research at, at NIST also coincided with, uh, increased use of plastics.
00:35:02.746 --> 00:35:03.166
Yes.
00:35:03.300 --> 00:35:09.766
that's why the fire service started to say, Hey, we're seeing fires occur a lot faster.
00:35:09.856 --> 00:35:11.246
We can't get there fast.
00:35:11.956 --> 00:35:13.876
and somehow they're growing faster.
00:35:14.302 --> 00:35:20.842
And so people started to say plastics and people started to say test methods.
00:35:21.536 --> 00:35:32.036
So the focus of this early science research on fires developing fast in a room flashover, how do test methods behave?
00:35:32.527 --> 00:35:42.646
So a lot of the research was focused on how does the, uh, so-called tunnel test in the US with fire down a, a tunnel like thing with a fire on a ceiling.
00:35:43.072 --> 00:35:44.713
how is that really working?
00:35:45.317 --> 00:35:49.260
how does, um, the cup burner work, Hmm.
00:35:49.492 --> 00:35:52.233
how does Fire on a Rod work?
00:35:52.436 --> 00:35:57.813
How does the, uh, test for you know, upward spread Hmm.
00:35:58.003 --> 00:35:59.643
a little material work.
00:35:59.822 --> 00:36:02.340
So there was focus on those things too.
00:36:02.800 --> 00:36:05.340
And that's what prompted work on flame spread.
00:36:05.500 --> 00:36:15.282
but you were trying to incorporate that, uh, with the, the full compartment size test, like the time to flash over the spread on a, on a carpet.
00:36:15.411 --> 00:36:22.161
So, so it was not just the material properties, it was, uh, a full scale physics of the whole compartment
00:36:22.161 --> 00:36:23.001
at fire, right?
00:36:23.313 --> 00:36:29.483
I think the focus on room fires, yes, flashover was a motivator in what that was.
00:36:30.067 --> 00:36:35.286
But when people started, modeling the fire, they didn't think they could.
00:36:35.936 --> 00:36:41.036
Put in all the aspects of fire spread do that correctly.
00:36:41.067 --> 00:36:44.434
They were still looked at independently, Mm-hmm.
00:36:44.769 --> 00:36:49.583
some people use FDS to model fire spread in a building today.
00:36:49.813 --> 00:36:50.782
I mean, you can do that.
00:36:50.782 --> 00:37:03.023
But there's a, there's a group called, there used to be a, a meeting annually, internationally where people came from all different places to show how they, applied fds.
00:37:03.364 --> 00:37:07.163
And I think, uh, Kevin McGrattan would cringe when he saw,
00:37:07.992 --> 00:37:13.643
Yeah, I, I, I also have very limited belief in modeling fire spread in fds.
00:37:13.643 --> 00:37:18.987
There are tricks that you can apply, and simplifications you can make, so it looks realistic
00:37:19.137 --> 00:37:23.177
you you can do it, you can, you can use the code to do that.
00:37:24.041 --> 00:37:26.802
but the question is, are you getting the right answer?
00:37:27.177 --> 00:37:27.597
in the.
00:37:27.601 --> 00:37:30.434
just, just a turbulent burning wall.
00:37:30.887 --> 00:37:38.114
when I saw fm, do that with their fire foam do that correctly to the data, I was impressed.
00:37:38.565 --> 00:37:42.581
more like that should be, my opinion, should be, done.
00:37:43.012 --> 00:37:43.302
I
00:37:43.932 --> 00:37:45.382
completely agree to that,
00:37:45.628 --> 00:37:55.525
you, have worked by Koseki done under Hirano , which are big fires and they show aspects of these big pool fires.
00:37:55.989 --> 00:38:00.224
I challenge the CFD people to reproduce that data.
00:38:00.351 --> 00:38:07.947
I, I still think even reproducing something as, as simple, if I may, as temperatures in, fire compartments, that's already a challenge.
00:38:07.947 --> 00:38:22.302
Like, whenever I see a paper that, uh, is a CFD paper and they show me a comparison with experiment, and they show, you know, this perfect, alignment of temperature, uh, between CFD and experiment.
00:38:22.302 --> 00:38:30.663
I, my first thought is that, that this is either made up or, or, or mistake because it's, it's, it's almost impossible to get this,
00:38:30.820 --> 00:38:31.460
correct.
00:38:31.769 --> 00:38:32.260
Yeah.
00:38:32.485 --> 00:38:35.405
maybe, maybe it's, it's not impossible.
00:38:35.454 --> 00:38:39.769
If you designed the experiment to fit the CFD model, Okay.
00:38:39.769 --> 00:38:40.449
This way is.
00:38:40.885 --> 00:38:48.514
designed the experiment, so based on the strengths of the CFD model, then you, you might get good results.
00:38:48.514 --> 00:38:56.197
I'm not saying CF I'm saying that there's aspects of it that need to be improved, especially for something like fire.
00:38:56.327 --> 00:39:11.182
1 interesting thing about the experiments you've carried at NBS that we're discussing today, today, your experiments, for example, the done, the one done with Steckler about the fires in compartments, but also the, the, corridor compartment experiments.
00:39:12.023 --> 00:39:16.503
These are staple validation cases for today's models.
00:39:16.853 --> 00:39:18.943
Have you, was this your intention?
00:39:18.943 --> 00:39:24.829
Have you foreseen that 40 years later, people will still refer to those as the, validation
00:39:24.829 --> 00:39:25.070
points.
00:39:25.688 --> 00:39:36.382
No, but I'm, I, I am impressed, with, there were CFD models before fds, uh, some of them out of Imperial College and uh, the Staler.
00:39:36.646 --> 00:39:44.086
experiments that we did, were basis of, trying to validate those c f D models.
00:39:44.827 --> 00:39:52.463
And as I said, the last time I had a look at this, this with a student, and we used FDS in the first shot.
00:39:52.472 --> 00:39:58.422
We didn't get it, get it right, because we stopped the grid at the doorway Hmm.
00:39:58.567 --> 00:40:05.766
then the students went on further and extended the grid outside the doorway and got some improved results.
00:40:05.797 --> 00:40:09.003
I forget the details of that, but published someplace.
00:40:10.072 --> 00:40:14.782
we didn't think it was going to be the b the basis to validate c f D models.
00:40:15.702 --> 00:40:32.615
It, it was to get a fundamental understanding before that, the only, results that were kind of over a wide range of conditions was done by and Joe Pr which were using water and salt water.
00:40:33.385 --> 00:40:37.775
So they, they were using water in salt water on a smaller scale.
00:40:37.896 --> 00:40:55.596
And we, we wanted to look at the, the large scale system and out of the small scale results, showed that as you changed the Reynolds number or something, uh, you got a different, flow coefficient to make the correction and work right.
00:40:55.831 --> 00:40:56.251
Hmm.
00:40:56.255 --> 00:41:00.925
And so we wanted to see if that would hold up, in more full scale, realistic.
00:41:01.585 --> 00:41:02.675
Flow conditions.
00:41:03.025 --> 00:41:09.574
That was more the motivation to try to, to extend, this work.
00:41:09.855 --> 00:41:12.215
Emmons did it in a nice, cute way.
00:41:13.094 --> 00:41:26.061
wanted to see if we could use, that time, the instrumentation that we were using was uh, pressure transducers that allowed us to measure in that low range accurately.
00:41:27.010 --> 00:41:28.391
And they were expensive.
00:41:29.050 --> 00:41:34.990
And I think it took me three years before I could buy enough of them to use in St
00:41:35.322 --> 00:41:37.887
H how many was there like, 10, 20.
00:41:38.208 --> 00:41:39.557
we might have had about 10.
00:41:40.190 --> 00:41:42.451
and then to measure the temperatures, right?
00:41:42.605 --> 00:41:54.137
we used, work that was done at fm, To investigate the accuracy of aspirated thermo couples where you put a thermocouple in a tube and you suck air over it.
00:41:54.827 --> 00:42:03.737
So when the, the air comes into that tube, you're measuring really the air temperature, at a high velocity over the thermocouple.
00:42:04.467 --> 00:42:10.427
if you just put the Therma couple in bear and you have a fire in hot walls, seeing radiation.
00:42:10.806 --> 00:42:13.007
how, how deep is the, the thermocouple into the tube?
00:42:13.007 --> 00:42:14.407
Is it at the beginning of the tube?
00:42:14.407 --> 00:42:15.967
Is it, uh, deep into,
00:42:16.237 --> 00:42:17.398
a beginning of, beginning
00:42:17.398 --> 00:42:19.668
so, so it's just a shielded thermocouple that
00:42:19.668 --> 00:42:21.438
aspirates the, good ther couple.
00:42:21.538 --> 00:42:21.958
Yes.
00:42:22.027 --> 00:42:26.268
I mean, you could make a Therma couple with a lot of baffles on it too, but then the baffles Hmm,
00:42:26.978 --> 00:42:27.467
okay.
00:42:27.728 --> 00:42:28.867
And re radiates.
00:42:28.867 --> 00:42:29.148
Okay.
00:42:29.188 --> 00:42:30.829
then radi radiates.
00:42:31.284 --> 00:42:35.434
uh, or you could use, you know, different size wires and I think.
00:42:36.309 --> 00:42:41.909
we tried different techniques and we, we said, oh, this technique is the best.
00:42:41.909 --> 00:42:42.230
Then.
00:42:42.719 --> 00:42:47.110
So when we did those experiments, we tried to do it in the best way possible.
00:42:47.246 --> 00:42:55.503
p tried to align the, bidirectional probes where the flow was going to be horizontal, you know, even though it's Yeah.
00:42:55.532 --> 00:42:55.773
this.
00:42:56.083 --> 00:42:58.655
And so we, we did the best, we could.
00:42:59.096 --> 00:43:02.695
Those experiments were done not on the NIST campus.
00:43:03.326 --> 00:43:12.429
They were done at a site that NIST inherited from a missile defense site with underground missiles.
00:43:13.202 --> 00:43:21.873
And so we got a building, on those grounds where we could do this and leave it set up for the whole time.
00:43:22.644 --> 00:43:25.755
That took some politics too, Hmm.
00:43:26.288 --> 00:43:36.757
in the missile pits later on, they were doing work on, I think Dave Evans was doing work on ceiling jets because it was a very quiet environment underground.
00:43:37.202 --> 00:43:50.440
so we, we had this extra, because not, I could not build a full scale room at nist, and if I went to the place where we had the big laboratory, we couldn't exhaust that easily.
00:43:50.550 --> 00:43:52.625
I mean, so it, it was tricky.
00:43:52.931 --> 00:44:05.291
So we, we got, know, permission to do these fire experiments, clean fires, and we, can move the, uh, fire plume around so we could show the effect of when you put it in there, a door or an narrow.
00:44:06.481 --> 00:44:08.951
or, you know, you would get different results.
00:44:08.951 --> 00:44:13.047
And so it, it was really gratifying work.
00:44:13.315 --> 00:44:15.534
the technician involved in that.
00:44:15.534 --> 00:44:30.661
Bill Rankin, lives in, uh, I think Northern Michigan on Lake His heritage is, from Finland and he became very close to Matt Kokola when Matt Kokola came and spent time with us.
00:44:30.751 --> 00:44:40.721
So in the eighties when I had my group, I invited a lot of people from abroad to come and integrate with our group and, and work.
00:44:40.847 --> 00:44:50.545
And, Matt Kok has with this guy Bill Rankin, and they did experiments of flames on ceilings that have all kinds of shapes.
00:44:50.684 --> 00:44:53.664
You, you maybe use, could see pictures of them.
00:44:54.545 --> 00:44:57.105
Someplace, but they're quite remarkable.
00:44:57.525 --> 00:45:01.864
And again, I don't think anybody has reproduced them by C f D.
00:45:02.195 --> 00:45:02.994
Beautiful.
00:45:03.438 --> 00:45:16.126
one thing I wanted to ask you, given the modern technology we got today, my generation of fire experiment, you know, laser velocity, fantastic.
00:45:16.126 --> 00:45:24.907
color, uh, devices, F T I R spectrometers that you can integrate into your, uh, smoke exhausts
00:45:25.188 --> 00:45:34.235
multi wavelength But, iso, when they were looking at F T R R results for toxicity, laboratories couldn't get consistent measurements.
00:45:34.757 --> 00:45:36.998
You know, that No, I didn't know that.
00:45:37.338 --> 00:45:39.057
to the people on a toxicity committee.
00:45:39.425 --> 00:45:43.746
I, I'm, I'm actually, uh, going to have David per soon into the, the podcast.
00:45:43.746 --> 00:45:45.545
I'll ask him about that.
00:45:45.813 --> 00:45:51.456
I don't think F D I R was current in David Pursers time, but please say hello to him.
00:45:51.916 --> 00:45:52.846
I will, I will.
00:45:53.070 --> 00:46:09.170
but, but Jim, the, the question is like, if he could like pick one tool of the modern fire science and, and tr try travel it to the eighties, like, uh, what do you think is the coolest thing we, we have now that you struggled with in the past that way Maybe we don't appreciate
00:46:09.269 --> 00:46:12.615
Well, when you mentioned lasers, Yeah.
00:46:13.076 --> 00:46:17.400
there, are, many ways of the combustion.
00:46:17.400 --> 00:46:28.429
People have learned how to measure things in flames, Inside?\ The inside flames, even look at, uh, The temperature at points and things like that.
00:46:28.480 --> 00:46:41.512
So there, there are many type diagnostic techniques that allow you to see things in flames probably people should start applying to fire you,
00:46:41.512 --> 00:46:47.282
you, you have mentioned research like, Prahl and Emmons uh, flows through openings.
00:46:47.452 --> 00:46:51.802
Uh, that, that's actually one of my favorite research pieces from 1975.
00:46:51.802 --> 00:46:52.402
Amazing.
00:46:52.543 --> 00:46:56.782
piece and fundamental piece of research for, for practical, for engineering.
00:46:57.052 --> 00:46:58.943
Well, yeah.
00:46:59.295 --> 00:47:00.096
saltwater.
00:47:00.416 --> 00:47:17.057
and again, with, with Steckler, we looked at saltwater, work, later on In fact, my colleague Andre uh, at Maryland when he joined Maryland, he got the salt water tank that I salvaged from this cause they were gonna throw it away.
00:47:17.958 --> 00:47:25.106
And, he did very fundamental work and he did work on, ceiling jets in which he did it with salt water.
00:47:25.563 --> 00:47:32.612
And he measured the velocity and, salt concentration so he could relate it to temperature.
00:47:33.072 --> 00:47:37.690
And that work is quite unique, and advanced for its time.
00:47:38.690 --> 00:47:41.208
But, it was never, extended.
00:47:41.594 --> 00:47:42.994
look look at what.
00:47:43.867 --> 00:47:47.186
Marshall did with salt water on ceiling jets.
00:47:47.376 --> 00:47:54.289
And that was, that was like an extension of all of this work from the seventies and eighties.
00:47:54.789 --> 00:47:59.130
And someone like Andre Marshall when he came to Maryland appreciated that.
00:47:59.579 --> 00:48:14.030
That's why I think the Chinese are going to get into it, because I see papers by young Chinese I see that they're reading the literature very carefully.
00:48:14.411 --> 00:48:33.179
Now, whether they're supervisor is forcing them to do this they're doing it based on their own, kind of motivation and the resources that exist around them at U S T C, they seem to have a respect and an embracement of, of that work.
00:48:33.547 --> 00:48:44.005
if they have that and they carry it forward, I see that there's, there's a, a linkage there that improve, fire research through the work in China.
00:48:44.344 --> 00:48:47.184
I hope we don't go to war before that time.
00:48:47.974 --> 00:48:48.724
Uh, please
00:48:49.083 --> 00:48:53.204
don't, don't enough politics in, in here.
00:48:53.204 --> 00:48:55.043
I hope that's not the case ever.
00:48:55.373 --> 00:48:59.003
Uh, where, where is horrible, what I've meant when I started this.
00:48:59.003 --> 00:48:59.844
Is this with the
00:48:59.873 --> 00:49:00.994
to study history.
00:49:01.143 --> 00:49:01.653
Of course.
00:49:02.335 --> 00:49:14.297
but, uh, I, I think there finishing this episode on this, on this beautiful experiments you've you've conducted at NBS that, that were cornerstone for many further achievements of fire science.
00:49:14.666 --> 00:49:18.143
one, one experiment, uh, that I, I didn't mention Okay?
00:49:18.153 --> 00:49:21.673
work by Jerry Faith on turbulent wall fires.
00:49:21.893 --> 00:49:22.384
Okay?
00:49:22.717 --> 00:49:29.590
and he had a student, I think that student passed away early, but, he did work on turbulent wall Mm-hmm.
00:49:29.804 --> 00:49:34.443
first he did like just hot plumes along the wall.
00:49:34.856 --> 00:49:38.001
Then he did the laminate fire along the wall.
00:49:38.090 --> 00:49:44.710
So he did, you know, can I get data for a laminate fire against the Hmm.
00:49:45.251 --> 00:49:46.931
And how did he make those fires?
00:49:47.094 --> 00:49:49.083
He made them in a simple way.
00:49:49.853 --> 00:49:52.923
He wanted to predict the burning rate of those fires.
00:49:53.733 --> 00:50:07.353
So he used, liquid fuel embedded into the wall where he could then know the evaporation, thermodynamics of that liquid, which is very simple kind of Hmm.
00:50:07.963 --> 00:50:10.204
You don't have to worry about spiralizing wood.
00:50:10.650 --> 00:50:16.507
And so if he knew that, he knew the burning rate very, very well.
00:50:17.391 --> 00:50:24.117
so, they developed a theory for the laminate flame, uh, using B number type Hmm.
00:50:24.829 --> 00:50:33.351
and they measured the temperature very carefully with, fine thermo couples and the velocity with, I think they used, uh, hot Wire.
00:50:33.692 --> 00:50:39.152
But they, Jerry Faith was a, a really excellent, mean, he was, he was unbelievable.
00:50:39.592 --> 00:50:42.541
uh, he was the editor of Combustion in Flame.
00:50:42.541 --> 00:50:46.431
He was the editor a journal, uh, in Fluid Mechanics.
00:50:46.431 --> 00:50:49.672
He was, he, he was remarkable person.
00:50:50.211 --> 00:50:52.012
and so this was very careful work.
00:50:52.012 --> 00:50:57.889
And then they extended it to the turbulent, field above it, with the same student.
00:50:57.889 --> 00:51:00.728
And they made the same measurements and they made the same.
00:51:00.789 --> 00:51:10.818
And they had a turbulent model that they, that they used, and got reasonable predictions even though they realized that there was a lot of radiation in those flames.
00:51:11.581 --> 00:51:13.860
and they swept that under the rug a little bit.
00:51:14.320 --> 00:51:19.594
But th that's a, that's a point where someone needs to go further.
00:51:20.083 --> 00:51:24.884
you see, like the next step would've been, let's see how we could bring in the radiation.
00:51:24.884 --> 00:51:26.643
Let's see how we could predict it.
00:51:27.137 --> 00:51:29.856
how is that a function of the fuel were burning?
00:51:30.704 --> 00:51:31.704
it be generalized?
00:51:31.804 --> 00:51:33.583
Can we get a simple equation?
00:51:33.673 --> 00:51:38.864
Or do we have to resort to CFD every time we wanna learn something?
00:51:39.155 --> 00:51:41.423
those steps never were taken anymore.
00:51:42.054 --> 00:51:49.784
I, I hope there are a lot of young researchers listening who, who, who, who seek their careers.
00:51:49.804 --> 00:51:50.534
Yeah, yeah.
00:51:50.534 --> 00:51:50.773
Yeah.
00:51:51.393 --> 00:51:59.797
And there is so many experiments that need to either a step further or maybe a revisit with a friendly update in a, uh, in the specs.
00:52:00.222 --> 00:52:04.351
like any field, if you throw money at it, people will do stuff.
00:52:04.929 --> 00:52:07.088
are not throwing enough money at fire.
00:52:07.809 --> 00:52:09.489
throwing money at batteries now.
00:52:09.588 --> 00:52:10.668
But, uh, Hmm.
00:52:11.199 --> 00:52:16.009
I don't think the industry cares, just like the plastic industry didn't care.
00:52:16.289 --> 00:52:17.599
So fire research fantastic.
00:52:17.599 --> 00:52:20.572
Was byproduct of, like you said, the the fines they
00:52:20.572 --> 00:52:20.811
got.
00:52:20.851 --> 00:52:30.521
the use of plastics, uh, was a technological change in the way we live that, enabled fire to develop in different ways.
00:52:31.311 --> 00:52:43.768
A and so, that was the, the spark really like batteries are now the, the spark that are saying, you know, we should do more fire research in batteries.
00:52:44.688 --> 00:52:48.079
So there, there will always be new technologies that come about.
00:52:48.349 --> 00:52:54.965
that will, you know, maybe people will invent fusion with those high temperatures, there will be a lot of fires.
00:52:55.385 --> 00:52:56.146
We'll see.
00:52:56.766 --> 00:53:06.545
The one thing I've learned after two years of doing this podcast, we create issues in fire quicker than, uh, than we generate solutions and people to who can solve them.
00:53:06.545 --> 00:53:08.786
So we are not gonna get out of job anywhere soon.
00:53:09.155 --> 00:53:23.251
No, the people in combustion may lose their jobs, but the people in fire will not because, and as I said, as investigators, uh, embrace this and the fire service embraces it, fire research should grow.
00:53:23.286 --> 00:53:23.909
Beautiful.
00:53:23.936 --> 00:53:27.695
let's end this, uh, episode with this, uh, with this thought.
00:53:27.916 --> 00:53:31.719
May maybe one more thing I'll, I'll maybe publish it separately.
00:53:31.719 --> 00:53:34.248
Like if you had a message to young people.
00:53:34.974 --> 00:53:36.463
Just coming into fire.
00:53:36.463 --> 00:53:40.864
There's so many young people coming into fire science more than ever before.
00:53:41.273 --> 00:53:46.994
So many faculties open, so many good places to pursue career in fire.
00:53:47.427 --> 00:53:57.887
Well, it's a stimulating field and it's a field that is rich in un discovery, so you can do a lot to contribute to it.
00:53:58.347 --> 00:54:11.443
But the reality is, is that I think a lot of young people have graduated through fire research curriculum, but they don't stay in the field the field is not embracing.
00:54:12.641 --> 00:54:12.920
a shame.
00:54:13.045 --> 00:54:29.139
If you, if you ask how many fire protection engineering firms hire fire scientists or people who did a, a, maybe a somewhat arcane to them research topic in fire, they won't be the first on their list to hire.
00:54:29.536 --> 00:54:29.623
Hmm.
00:54:29.909 --> 00:54:34.458
So, the field is not in need of science.
00:54:34.871 --> 00:54:38.572
The field is in need of tools to how to solve problems.
00:54:38.751 --> 00:54:40.641
Well, we can use scientists
00:54:40.641 --> 00:54:41.461
to, Yes.
00:54:41.481 --> 00:54:51.298
And the way that works is like, you know, if somebody says, let's go to the moon and people throw money on that, then, then you figure out how to get off this planet.
00:54:51.759 --> 00:54:54.659
But as soon as somebody says, who cares about the.
00:54:55.239 --> 00:54:56.159
you see what happens?
00:54:56.233 --> 00:54:56.844
mm-hmm.
00:54:57.148 --> 00:54:58.918
fire is in that vein.
00:54:59.179 --> 00:55:00.898
it's a drag on the economy.
00:55:01.088 --> 00:55:03.139
It's not a promotion of economy.
00:55:03.849 --> 00:55:08.199
so it's not like inventing a new thing and everything takes off.
00:55:08.199 --> 00:55:17.436
And, and now, now you, you have Silicon Valley, fire degrades from, a commerce and economics.
00:55:17.637 --> 00:55:18.505
It's a drag.
00:55:18.956 --> 00:55:19.675
it's a loss.
00:55:19.826 --> 00:55:29.161
But that's why I said if the fire, service community, the firefighters wake up say we need better tools That is, need science.
00:55:29.608 --> 00:55:30.809
that may be the savior.
00:55:31.514 --> 00:55:39.554
Lund is the only program that realizes this, that educates their people and then they go into the fire service.
00:55:40.186 --> 00:55:44.710
So that is one seed that I haven't seen Grow beyond Lund
00:55:44.949 --> 00:55:47.329
Now I, I, I see James, I see.
00:55:47.349 --> 00:55:49.188
See some promising seeds.
00:55:49.719 --> 00:55:55.268
Uh, fire, fire Safety Research Institute, ul, this, I, I really believe,
00:55:55.563 --> 00:55:58.106
I, know, I commend those guys I,
00:55:58.896 --> 00:56:08.195
I, really believe this will, this, this is a thing and yeah, let's well, I hope that your prediction that, uh, the golden era is still in front of us.
00:56:08.239 --> 00:56:08.860
it's there.
00:56:08.931 --> 00:56:21.416
I mean, look, it took Hottel and Emmons a long time to get, you know, some activity going in fire, so, It's there, is always going to exist on this planet.
00:56:21.800 --> 00:56:26.530
And the as the need to understand it grows, the science will grow.
00:56:26.626 --> 00:56:27.425
Fantastic.
00:56:27.583 --> 00:56:28.699
Thank you very much.
00:56:29.175 --> 00:56:29.746
And that's it.
00:56:29.775 --> 00:56:33.536
This concludes the whole interview I had with professor James Quintiere.
00:56:33.945 --> 00:56:44.655
I'm really thankful to James for spending so much time with me and sharing so much of his thoughts about the us fire science, how it developed, how it grown.
00:56:45.262 --> 00:56:53.300
How it changed over the years and maybe some inspiration in How we can go back to the glorious times of the fire science research.
00:56:53.485 --> 00:57:00.264
In today's episode, we've talked a lot about how the experiments were carried and I think a good message to everyone listening.
00:57:00.264 --> 00:57:02.005
The researchers listening is that.
00:57:02.394 --> 00:57:04.045
Many of those experiments.
00:57:04.585 --> 00:57:06.175
Are done in Hades.
00:57:06.534 --> 00:57:10.135
Like 40 years ago and they are still this stable.
00:57:10.331 --> 00:57:13.420
Cases for validating our models.
00:57:13.780 --> 00:57:15.280
It's it's astonishing.
00:57:15.400 --> 00:57:20.891
What long lasting impact you can achieve with carefully planned experiments and.
00:57:21.038 --> 00:57:23.257
Really well thought out fire science.
00:57:23.588 --> 00:57:35.378
It's a statement that's very contradictory to the modern science, where you're pushed to get papers published quickly, publish as many as you can, hopefully with high impact factors.
00:57:35.947 --> 00:57:39.367
Look, this is like the exact opposite end of spectrum.
00:57:39.398 --> 00:57:44.318
Doing a very carefully planned experiment, maybe taking a year or two, doing that.
00:57:44.378 --> 00:57:45.907
Publishing a single paper.
00:57:45.940 --> 00:57:47.860
Which still 40 years later.
00:57:48.221 --> 00:57:49.481
It's a basis of models.
00:57:49.481 --> 00:57:50.440
How amazing is that?
00:57:50.800 --> 00:57:52.721
If I had to choose.
00:57:53.050 --> 00:57:55.721
Between writing a really, really good.
00:57:55.728 --> 00:57:59.927
paper that we'll continue making impact in few decades and, and.
00:58:00.045 --> 00:58:01.844
popping Salemi slices of research.
00:58:01.844 --> 00:58:08.485
I, I would highly recommend doing the former, I guess this is something we try with our fire science.
00:58:08.545 --> 00:58:09.085
The ITB.
00:58:09.474 --> 00:58:15.885
I'm not sure if we always accomplish that, we'll see in a few decades, but, Yeah, that's, that's something I aspire to and I highly.
00:58:15.998 --> 00:58:19.297
Recommend that to any academic around.
00:58:19.297 --> 00:58:24.701
And I hope this interview with James, Can serve as an inspiration on how to achieve that.
00:58:25.481 --> 00:58:28.481
Thank you very much for tuning into the fire science show.
00:58:28.811 --> 00:58:31.780
And there's more great episodes coming your way.
00:58:31.780 --> 00:58:34.380
So see here next Wednesday bye!.