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Showing posts with label FDS. Show all posts
Showing posts with label FDS. Show all posts

Friday, July 08, 2011

Call for papers: Fire Technology special issue on WTC Collapse

Fire Technology, the journal of the National Fire Protection Association published by Springer, is preparing an issue on the 2001 fire and collapse of World Trade Center.

The purpose is to collect research, forensic and engineering output of the highest scholarly standards synthesized in the 10 years passed since the event.

Multidisciplinary and international contributions are especially encouraged. Topics of interests include: WTC 1, 2, 5 and 7, the crash, fires, structural response, collapse, forensic conclusions, experiments, modelling, Fire and Rescue intervention, human behaviour, building design, post-collapse fires and recovery, previous attacks on WTC and related subjects.

Submissions will be accepted until 11th Nov 2011 at: http://fire.edmgr.com (choose article type "World Trace Center") .

The call for papers flyer can do downloaded here. Please spread the word, we are looking for a wide range of high quality submissions.

For further information, contact the Associate Editor of this special issue: G.Rein@ed.ac.uk, Dr Guillermo Rein, The University of Edinburgh.

A New York City fireman calls for 10 more rescue workers to make their way into the rubble of the World Trade Center. Photo form Wikipedia, United States Navy ID 010914-N-3995K-01

Thursday, October 14, 2010

Heron Tower and the begining of the concept of travelling fires in design

A recent article about Arup's fire design of Heron Tower (among the tallest buildings in London) appeared in Info4fire.com. The Heron Tower project won the Fire Safety Engineering design category at the Fire Excellence Awards in May 2009.

14 September 2009, Info4fire.com

Heron Tower is a landmark in our collaboration with Arup since it led to a joint PhD thesis and a series of papers. Since 2007 we are working together to define novel design fires in similar large spaces to that in Heron Tower. We came up with the concept of "travelling fires". The initial work was presented at Interflam 2007.


Figure: Snapshot from the fire model using FDS published here. Temperature map for a 500 kW/m2 well-distributed fire on the bottom floor with top and bottom floor ventilation. The atrium acts as a chimney, linking the bottom and the top floors.

Since then, the research has advanced significantly and led to several other papers and case studies. We recently published an overview and a building survey in the magazine Fire Risk Management. The key element behind this research is the need to provide design solutions to the large parts of modern buildings that fall outside the limits set out in the Eurocodes.

The two articles published in Fire Risk Management led to an unusual number of Letters to the Editor. Letters from Mike Wood, Pilkington Group, and from Dr Kirby, Sirius Fire Safety Consultants, were received. This and this were our respective replies (our reply to Dr Kirby is also attached below).

NOTE: Thanks to Chris for mentioning the article.


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On Fire Risk Management Feb 2010, Dr Kirby from Sirius Fire Safety Consultants commented on our article "Out of Range".

Our reply, Beyond Limits, in Fire Risk Management March 2010 read:
We are pleased to read the letter that Dr Kirby, from Sirius Fire Safety Consultants, wrote in response to our December cover article, "Out of range". In our article, we reported a survey of 3,080 compartments on the campus of the University of Edinburgh buildings underlining the compartment volume that falls inside of the design fire specifications of current Eurocode 1 (66 % of the older buildings, but only 8% of the most modern one). Instead of volume, Dr Kirby prefers to quote our results as % of the number of compartments (95 % of the older buildings, but only 63% of the most modern one), assuming perhaps that all compartments are equally important regardless of the very large differences in size (e.g., atria vs. single desk office). But the main conclusion of our article, that the modern building contains a very large portion of built environment outside the limits of the Eurocode, stands true no matter what survey quantity is quoted.
Dr Kirby also refers to the UK National Application Document which extends beyond the Eurocode 1 range and without limit, the use of these post-flashover design fires. We consulted this document while investigating the technical origins of the Eurocode, but after two years of searching and requests, we have not been able to find a copy of the validation work it cites. If Dr Kirby or any reader of the FRM magazine could kindly send us a copy of the validation work, we would be grateful. We hope that full details of these studies are made available to the fire research community at large for the benefit of all.
We agree that Eurocode 1 is a good document and a first step putting fire engineering into a codified form. We appreciate Dr Kirby's kind words of support for research in alternative design fires. His comments on fuel-control fires in large compartments resonate very well with our previous article in this publication ("Travel guide", November 2009, pp.12-16 by J Stern-Gottfried, G Rein and J Torero). In that article, we highlight that in large compartments, a post flashover fire is not likely to occur, but that a travelling fire spreading across the floor plate should be considered instead. We think that in the future travelling fires should also be considered as design fires and compliment the current Eurocode. Work conducted to date is available and easily accessible to the fire research community at large for the benefit of all.
Dr Guillermo Rein, BRE Centre for Fire Safety Engineering, The University of Edinburgh

Friday, July 30, 2010

Research and the release rate of FDS versions

I have recently posted in the Discussion Group site for FDS and Smokeview some questions related to the release rate of FDS versions that I would like to post here as well.

Note: Fire Dynamics Simulator (FDS) is a computational fluid dynamics model of fire-driven fluid flow developed by NIST.


First, note that I am not a code developer but an user. I am a particular type of user: a researcher. An academic who studies methodologies to use some of the tools available to fire safety engineers. Hopefully I have helped or will help to develop the state of the art in fire modelling. I certainly support improvements to FDS and greatly admire the work of the FDS developers team.

For the last two years I am facing two problems stemming from the different versions of FDS that are released with some frequency. Research (my research at least) has a characteristic time that seems to be significantly longer that the time between version releases. This means that when we start a research project on modelling that includes FDS we use the newest version available but by the time the work is finishing and concluding, there are one or two new versions of FDS available. Note: PhD thesis in the UK last for three or four years.


This has led to these issues in my research group:

I - Different results from different versions
We have accidentally observed two times already (in two different PhD thesis work) that the same input file produces significantly different results in different but consecutive versions of FDS (eg v5.2.0, v5.2.5 and v5.3.0). In one case it took us months to figure out the problem. Both of these problems were discussed in due time in the FDS forum. My personal recommendation to my students is that they fix the FDS version of their interest at the beginning of the project and stay with it until the very end of the thesis.

I wonder if other researchers would like to express their views on this issue?

II - Peer reviewed of FDS results
We have had reviewers complaining and requesting rejection of our modelling papers because results are not in the latest version of FDS. NOTE: just the review process in fire and combustion typically takes anything from 3 to 16 months.

About modelling work on the Dalmarnock Fire Tests (Chp 2 of this thesis), one anonymous reviewer recently said "Given that [version] 5 has significant changes in the combustion model and other submodels, there is no value to the community in publishing a paper on FDS 4 unless the paper can demonstrate that the conclusions on FDS performance will remain valid for the current version and versions under active development".

To demonstrate that the conclusions of the work apply to the newest version of FDS effectively implies repeating the thesis work. This is not affordable in most cases, at least not for my group. Should academics fear every new version of FDS because it means one extra year of work for PhD students?

I wonder if other researchers would like to express their views on this issue?

III - Corollary
Following from issues I and II, I am confronted with the question, what happens with buildings which design was aided and approved using previous versions of FDS. What are the implications to forensic investigations that reached conclusions in court using a previous version of FDS?