Typically, the UMD Department of Fire Protection Engineering hosts an Annual Christmas Tree Fire Safety Demonstration - a demo consisting of a series of live fire experiments on both natural and artificial Christmas trees to show the burning behavior of typical Christmas tree fires. These experiments, led by Isaac Leventon, demonstrate the impact of moisture content on ignition, fire growth rate and peak burning behavior – proof that it is vital to maintain well-hydrated trees.

Due to current conditions of the pandemic, we won't hold a media day this year, however, Dr. Leventon will still hold the tree fire-size predication competition! Please read on below ~   


 

The Competition

Students, faculty, researchers and engineers from fire safety programs around the world are invited to join the "burning behavior prediction" competition - of a Balsam Fir Christmas Tree. The highest individual and highest group scores - i.e., the average scores of all submissions from a single research team or program (min. 3 team members) - will be announced to all competition participants and the research team (from a University or Research Institution) with the highest average group score will also earn the coveted Golden Pinecone Award.
 
The competition burn will commence at 12:00 pm on December 22, 2020; the event will be livestreamed for all participants. Our current reigning champions are the members of University of Queensland Fire Safety Science and Engineering Program. Hopefully someone new can dethrone them and earn the Golden Pinecone this year!
 

How to participate: Generating and submitting your predictions

This year, the submission (and generation of) predicted heat release rate (HRR) curves will once again be made possible by visiting https://pages.nist.gov/christmas_tree_fire_safety/. Here, you can use a custom-made app that allows you to ‘build’ (and submit) your own fire by adjusting just four parameters that define:

  • Fire Growth Rate
  • Peak Heat Release Rate (Peak HRR)
  • Duration of Steady Burning
  • Fire Decay

In this app, after you click submit, an email will be generated that contains the four parameters defining your HRR curve. In this email, please remember to add your name, email and lab affiliation if you wish to receive credit (and final competition results) and CLICK SEND so that we receive your submission.

If you prefer the old system – submitting HRR predictions in massive spreadsheets or .txt files – you may submit those files directly to TreeHRR@nist.gov. These prediction files should be formatted in two columns with a 1 Hz resolution in the format: [time (s) | HRR (kW)].

The Scoring SystemData table from 2019 Christmas tree fire burn.

This year's competition will be organized and scored a bit differently from previous years. After a conversation with a colleague at NIST, we've decided to make a first order attempt at using this competition to contextualize model-predictions vs. experimental uncertainty.  This competition is meant to be fun for the community (and to  share an important holiday fire safety message), but it also offers a teachable moment: experimental measurements have an inherent uncertainty and our ability to accurately predict (fire behavior of interest) should always be assessed with explicit considerations for this uncertainty.

In short, this means that tests will be repeated in triplicate and your predictions will be scored with respect to the average and standard deviations (with explicit considerations for measurement uncertainty) of experimentally measured burning behavior (i.e., peak HRR, time to peak, fire growth time and duration, and total energy release).

Points (100 possible) will be awarded in 5 categories as listed below. Our scoring system will give up to 20 points for each category so long as the predicted values are within two standard deviations considering the calculated uncertainties. 

Description

Uncertainty calculated as:

Peak Heat Release Rate

Propagation of error includinguncertainty in time-resolved balance reading and
heat of combustion

Total Energy Release

Propagation of error includinguncertainty in time-resolved balance reading and
heat of combustion  

Time to Peak Heat Release Rate

Standard deviation of time to
peak HRR values measured in each
of the 3 repeated tests

Duration in which HRR exceeds 80% of peak HRR

In each test, a lower and upper estimate of the duration of burning in which HRR exceeds 80% of peak HRR can be made based on the uncertainty in measured HRR. These two values are shown graphically in Fig. 1.

Uncertainty in 80% duration is thus calculated as the standard deviation of all 6 of these values measured from each of the 3 repeated tests.

Duration in which HRR exceeds 50% of peak HRR

Calculated identically as the
uncertainty in 80% duration

Acknowledgements:

Dr. Leventon would like to thank Dr. Anthony  Hamins of NIST for his thoughtful comments and helpful suggestions in conversations leading up to this year's event.

 


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