210 - Fire Fundamentals pt. 16 - Turbulence with Randy McDermott

Fire Science Show

Content provided by Wojciech Wegrzynski. All podcast content including episodes, graphics, and podcast descriptions are uploaded and provided directly by Wojciech Wegrzynski or their podcast platform partner. If you believe someone is using your copyrighted work without your permission, you can follow the process outlined here https://podcastplayer.com/legal.

1M ago 58:20

MP3•Episode home

In the 16th part of the Fire Fundamentals series, we invite Randy McDermott from NIST to join us for a deep dive into turbulence and its critical role in fire dynamics modelling. We explore the physics behind turbulent combustion and how it fundamentally shapes fire behaviour, plume dynamics, and simulation accuracy.
In this episode we cover:

Defining turbulence as the enhancement of mixing and heat transfer through the creation of eddies and instabilities
Understanding length scales in turbulence from the integral scale to the Kolmogorov scale
Practical considerations when choosing grid resolutions for different fire engineering applications
How turbulence models work in Large Eddy Simulation (LES) and what they represent
Limitations of the D* criterion for mesh sizing and why higher resolution may be needed
Differences between pre-mixed and diffusion flames in turbulent combustion
Time scales in fire and the concept of Damköhler number in determining combustion behaviour
Entrainment physics at the base of fire plumes requires centimetre-scale resolution
Why turbulence modelling ultimately determines the accuracy of fire simulations

----
The Fire Science Show is produced by the Fire Science Media in collaboration with OFR Consultants. Thank you to the podcast sponsor for their continuous support towards our mission.

Chapters

1. Introduction to Fire Fundamentals (00:00:00)

2. Defining Turbulence in Fire Science (00:02:40)

3. Modeling Turbulence with DNS and LES (00:09:39)

4. Length Scales and D-Star Criterion (00:17:45)

5. Turbulent Combustion Fundamentals (00:23:45)

6. Time Scales in Fire Dynamics (00:32:40)

7. Entrainment and Plume Dynamics (00:39:20)

8. Practical Applications and Resolution Requirements (00:48:50)

9. Episode Wrap-up and Key Takeaways (00:55:15)

222 episodes

#Science #Tech #Physics #Wojciech Wegrzynski #Fire #Smoking #Wildfires #Cfd #Safety #Risk #Civil Engineering