Fire dynamics calculations are not going to help, except in a very general way. The error bars associated with fire dynamics equations are huge, on the order of plus or minus 60%. See Figure 22.4.9.3 b in NFPA 921, reproduced as an attachment here.

There is plenty of stupid going around, but failing to perform calculations is not the problem. Failing to understand fire dynamics, or the basic units of energy and power and flux is the major symptom of incompetence in fire dynamics. Check out this deposition by a person who claims a degree in fire science testifying in a capital murder case:

Page 10
Q. If you would, state your theory as to the origin and cause of the fire .
A. The origin of the fire was in the crawl space below the master bedroom, which is the left front room. The cause of the fire was initiated from a propane weed burner and direct contact with the building construction of the floor.
Q. And what is your theory as to how the propane weed burner was ignited?
A. Human factor.
Q. And am I correct in saying that your opinion states that this fire was an arson?
A. That's correct, sir.

Page 281
Q. Okay. What's the basic unit of energy called?
A. I'm unsure at this time.
Q. You ever heard of a joule?
A. I have.
Q. What is it?
A. It's a measurement of energy or that's how – it has to do with electricity as well.

Page 282
Q. What are the basic units of power called?
A. AC and DC.
Q. I'm sorry?
A. AC and DC.
Q. Have you ever heard of a watt?
A. Yes, sir.
Q. Would that be the correct answer?
A. More than likely.
Q. What is a watt?
A. I mean I'm unsure. If you want me to look at a manual and give you these answers --
Q. No, I'm asking you --
A. Off the top of my head, I mean you're asking --it's like I'm taking a quiz right now over --
Q. You're taking a deposition.
A. I understand that. But you're asking me questions that are found in a manual.
Q. Do you know what a watt is?
A. No, sir.
Q. Okay. How is the size of a fire measured?
A. I'm unsure at this time.
Q. Okay. What is radiant heat flux?
A. I'm unsure at this time.
Q. What is air entrainment?
A. I'm unsure.
Q. What is a ceiling jet?
A. Unsure.

Page 275
Q. What does pyrolysis mean?
A. Basically the -- like wood will distort, take a different shape. It will -- pyrolysis is -- the wood is igniting and then the change of the wood is showing like charred and things like that.

Page 277
Q. Do you know how many BTUs are present in a typical cubic foot of propane?
A. Not at this time.
Q. Do you know what the chemical formula for propane is?
A. I'm unsure at this time.
Q. Can you write down the chemical equation that describes the burning of propane in air?
A. I'm unsure.
Q. How many volumes of oxygen are required to burn a volume of propane?
A. Unsure.
Q. How many volumes of air are required to burn a volume of propane?
A. Unsure.
Q. Have you ever tried to set wood on fire using a propane torch?
A. No, sir.
Q. Do you agree that there’s both a liquid phase and a vapor phase inside the propane tank?
A. Yes, sir.
Q. Do you know how much vapor a given volume of liquid produces?
A. No, sir, unsure at this time.

I have a collection of these depositions, which generally occur just before the case is settled or the charges dismissed, as they were in this case.