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RobTipples
Posts: 36
Registered: ‎07-19-2013
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Friday challenge - Creating fire

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03-28-2014 07:10 AM

Hi guys, I'm going to try and create a marketing image of some flames around a stubby pringle tube shaped object. It's my intention to do this by creating some sort of CFD simulation.

 

Once I've got a good distribution, I'll export various isosurfaces to Showcase where, by tweaking colour, transparency, glow etc. I can layer them up to look like flames.

 

Assuming that there's no point asking if anyone else has done anything similar, can anyone think of a good simulation that I can run to get the unstable plumes that I'm after?

 

I'm currently thinking of some sort of multiple point heating.

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hartogj
Posts: 215
Registered: ‎08-03-2011

Re: Friday challenge - Creating fire

03-28-2014 07:38 AM in reply to: RobTipples

Hi RobTIpples

 

Happy Friday.

 

As I'm sure you know, SimCFD doesn't directly model the chemistry here. But you can set up a simulation in a way that roughly represents a flame with heat generation conditions. We have worked with clients looking to approximate flames at varying levels of detail and in many cases have matched up fairly nicely when working with a known fire size and shape. One thing to be aware of is that it won't be easy to model radiation directly from the flame region, so flames burning at the right size and temp to be strong emitters aren't easy to replicate. However for flames at a modest size you should be able to do fairly well, especially if this is just a marketing image.

 

The attached image is an example of what's been done for marketing in the past. This is a very simple setup - it is just heat generation in a region above the solid blocks. The transparent purple region is a scalar iso surface that represents the flame. Some notes on this example:

 

1 - A scalar BC was assigned on a surface just above the blocks where air was being drawn into the flame. This 'marked" the air as a flame region and naturally dissipated as the air rose above the flame.

2 - This image could offer a richer visualization of the flame region by using multiple scalar iso surfaces (rather than just one) using orange, white, and blue hues instead of yellow

3 - Showcase doesn't handle transient results so I think I would stick to steady state (unless you are very clever and very patient with lots and lots of different frames and shots)

 

Let us know how this comes along. If it's for marketing, would you be open to sharing some of the results?

 

Jon

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Contributor
RobTipples
Posts: 36
Registered: ‎07-19-2013

Re: Friday challenge - Creating fire

03-28-2014 07:42 AM in reply to: hartogj

Clearly I shouldn't have assumed that no one had done this before! Thanks for the help Jon!

 

I'm only doing this when I've got little bits of time, but I'll make sure that I post something up when I've got it!

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