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lin December 19, 2004 02:42

Species transport
Hi Everyone,

Who could help me about the species transport with Phoenics?

I try to calculate the species such as odors dispersion in a block. I do not know how to input the species parameters in the inlet with VR windows.



lin December 19, 2004 02:45

Re: Species transport

leon mills December 19, 2004 20:59

Re: Species transport
Try setting the contaminant (C1) source in the inlet term. Set this with the density, concentration, and temperature as required.

C1 is set as a scalar so 100 could be 100 ppm or 100 ppb, just remember the sale used for the outputs.

There is a library case in the tutorials that looks a dispersion of fumes from a car park exhaust.

Hope this helps,


Hervé December 20, 2004 09:50

Re: Species transport
Sorry if this reply is not fully appropriate. I am just concerned by the units inferred here. "PPM" and "PPB" refer to volumetric fractions (respectively "parts per millions", and "parts per billions", I assume).

I would have thought that unless a dedicated transport equation for volumetric quantities (i.e. with a specific additionnal source term), the default unboarded equation was recommended only for massic quantities. Therefore, C1 in kg/kg would be more suitable.

Indeed, once solved, C1 values can be converted, wia the density, to any of their counterparts volumetric quantities. In Phoenics, if not part of the core code, it can be easily done in storing for instance C1PM or C1PB and add the appropriate Fortran additional coding.

Hope it helps.

leon mills December 21, 2004 00:54

Re: Species transport

You are correct. I have set this up in my file and forgot that C1 should be represented in kg/kg or something similar then converted to ppm...


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