Archive for Resources

New web calculator – t-squared fire ramp generator

Wondering when an ultrafast t-squared fire reaches 2,000 kW? 104 seconds! Or just want to quickly generate a slow t-squared curve to use in FDS? I’ve posted a new web calculator tool to generate t-squared fires, output plots, CSV files, and FDS syntax.

The t-squared fire ramp calculator is available here:

http://www.koverholt.com/t-squared-fire-ramp-calculator/

Please let me know if you find any bugs, would like to give feedback on this tool, or have a request for another web calculator!

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How to compile CFAST on Mac OS X and Linux

The Consolidated Model of Fire and Smoke Transport (CFAST) model is a two-zone fire model developed by NIST. From the NIST website, you can download the Windows version of CFAST, which includes a graphical user interface frontend (CEdit) for the creation and execution of CFAST cases. However, there are no downloadable CFAST binaries or user interfaces for the Mac and Linux platforms; you must compile CFAST yourself.

This guide will help you compile the CFAST executable on Mac OS X and Linux. This is useful for running CFAST cases on Mac or Linux machines, which is especially useful for scripting CFAST runs for optimization problems or running CFAST on a large number of cases in batch mode.

You will need the Intel Fortran compilers (ifort) and a copy of the CFAST source code from the CFAST Google Code site. You can try to use other free compilers, but I find that the Intel compilers are the most compatible and produce the most optimized (fastest) binaries. Note: there are heavily discounted Intel compilers for students.

To download the CFAST source code, the easiest way is to install subversion on your Mac or Linux machine and issue the following command:

svn co http://cfast.googlecode.com/svn/trunk/ cfast

Once you have the CFAST source code on your machine, you can perform the following steps to compile the CFAST executable.

1. In the cfast/CFAST/ directory, edit the makefile_linux file and make the following changes:

  • Replace ‘radation’ with ‘radiation’; this is a typo
  • Add ‘cyl_conduct.o’, ‘datamodules.o’, and ‘ssHeaders.f’ to the obj_serial section
  • Add the following lines to the Object Dependencies section:
    • cyl_conduct.o : cyl_conduct.f
    • datamodules.o : datamodules.f90
    • ssHeaders.o : ssHeaders.f
  • Add ‘cyl_conduct.f’, ‘datamodules.f90′, and ‘ssHeaders.f’ to the cfast.o line

Note: The corrected makefile can also be downloaded from here.

2. Copy datamodules.f90 from the cfast/CFAST/Include/ directory to the cfast/CFAST/Source/ directory

3. Change to the cfast/CFAST/Source/ directory

4. Run the command ‘ifort -c datamodules.f90′ to compile the datamodules and iofiles modules

5. Finally, run the command ‘make -f ../makefile_linux intel_osx_64’ to build CFAST

5b. If you are running Linux, the command is ‘make -f ../makefile_linux intel_linux’

Using these steps, I was able to build CFAST on an Intel Macbook Pro running 10.6 (Snow Leopard) as well as a Linux machine running CentOS release 5.6 with the 64-bit Intel Fortran Compiler version 12.0.4.184.

With your new CFAST executable file (cfast_osx_intel_64), you can run a CFAST case using the following syntax:

./cfast_osx_intel_64 casename

where casename is the name of your CFAST casename.in file (notice the .in file extension is omitted from the command).
Happy modeling!

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Apartment fires burn and homes are lost due to outdated modes of thought

[Used from KPRC video click2houston.com]

Fire. It’s what I do. And I happen to subscribe to Google News alerts that have “Houston Fire” in the title. Helps me keep in touch with the fire. It also helpingly disturbs me as to what actually goes on outside of the classroom. Really, it’s quite a good way to keep yourself thinking and valuable if you are stuck with that stagnant smell of your job or classes.

Lots of fires happen everyday. Apartment fires always happen. A lot. Three apartment complexes burned to the ground within 48 hours over the past weekend. And then some. This is what I see:

Residents Say They Heard Gunshots Before 3-Alarm Fire

Blaze damages second apartment complex in 24 hours

Fire erupts at SW Houston apartments

Apartment Blaze Damages At Least 16 Units

Apartment fire sends 5 to Hospital

Yes, those are the most recent stories in my warm and cozy feed reader.

When is legislation going to get off of its ass and move at the pace that the rest of us do? When is enforcement going to follow? Sure, I guess we all are biased to the field that we are in and think that it is the most important thing in the world. But seriously, people are dying and losing their homes in the midst of an ocean of politics and code books wasting valuable daylight.

Southeast Houston Apartment Fire

[Picture used from myFoxHouston.com]

A lot of the time, I am an optimist. I see what change has followed the positive move of a community-based and collaborative internet (see video in previous post) in other industries. And then I imagine progress and change happening in our daily lives. I dream of governmental processes being way more open and community-driven than we are used to. I can watch it in real-time, play-by-play happening with larger corporations – as they break down due to the epidemic spread of knowledge and awareness. And I imagine a world where fire sprinklers (technology that has been around for 130 years) and other fire safety systems make fire protection engineers obsolete before my industry has even had a chance to get popular and prestigious.

I suppose what I am saying is that I toil my soul, expand my brain, and work every breathing moment that I can, day-by-day on prediction of fire, contribution to the robust knowledge that we have on fire/combustion, and working using my technical skills. All of this to allow fire documentation, analytical and numerical tools, and scientific information to be available to all people around the world: engineers, scientists, students, and so on. Why? I’d say, in this century and society, I do it to contribute. And I think if just a few other key people did the same, our fire, death, and loss of home problems would vanish at amazing and mind-blowing speeds.

P.S. This thought process isn’t just limited to my field of fire science, but I write about it because it is what I do. Think about your field for a second. Finance, safety, technology, whatever it is. Mentally apply success to the field by working on and tweaking the top 3% of the people, systems, or methods that are in use now. Realize that these top 3% are there due mainly to tradition, and did not get there due to community-driven work.

Keep working at it. Align your work with your values. The change will happen. I’ll be waiting.

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