|
[Sponsors] |
July 15, 2021, 14:50 |
Questions on default Arrhenius factors
|
#1 |
New Member
Join Date: Jul 2021
Posts: 2
Rep Power: 0 |
Dear CFD community,
I'm quite new to Ansys and was wondering if there is a database or a text file with the sources of the used pre-exponential factors that can be found in Ansys. I tried searching the theory guide, but couldn't find anything. Another thing that boggles my mind are the units of these factors. The default Arrhenius factor changes significantly when choosing volumetric reactions (i.e. 2.239e+12 for carbon monoxide oxidation) and reactions on the particle surface (i.e. for solid coke oxidation 0.002). What kind of units am I seeing? The user manual only states that they are 'consistent units'. Sorry in advance if these questions do not fit this forum. Thanks! |
|
July 20, 2021, 03:07 |
|
#2 |
New Member
diegovda
Join Date: May 2016
Posts: 10
Rep Power: 10 |
Hello,
Fluent uses units of J, kmol, m, s. The units of the pre-exponential factors will depend on the number of species involved in the reaction rate equation and their reaction order. The pre-exponential factor will have the units that make the reaction rate be kmol/(m^3·s) in case of volumetric reactions and kmol/(m^2·s) if you are using surface reactions. I think that this is the meaning of 'consistent units'. I am sorry I cannot tell anything about the text file for the pre-exponential factors you are seeking. |
|
July 20, 2021, 09:15 |
|
#3 | |
New Member
Join Date: Jul 2021
Posts: 2
Rep Power: 0 |
Quote:
Thank you very much for the answer, at least the units are now clear for me. I guess I will look up the factors and see if they are quoted somewhere in literature. |
||
Tags |
ansys, arrhenius, cfd, factors |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Under-Relaxation factors for Simple Consistent method | Abhinav_Nagarajan | OpenFOAM Running, Solving & CFD | 3 | March 23, 2020 06:01 |
define volumetric reaction rate via UDF but how to set default Arrhenius rate | richard ben | Fluent UDF and Scheme Programming | 0 | May 11, 2013 09:05 |
Default interior breakdown recongnization | rmojgani | FLUENT | 5 | November 3, 2012 13:08 |
CFX problem in ubuntu (linux) | Vigneshramaero | CFX | 0 | July 13, 2012 11:22 |
CFD beginner:- Help needed, general questions on Free jets? (Fluent 5.2.3) | Wong, R.Y.T. | Main CFD Forum | 5 | October 22, 2010 01:51 |