|April 13, 2009, 15:59||
Help me for the simulation on hydrogen/air combustion
Join Date: Apr 2009
Posts: 4Rep Power: 8
I am puzzled by the simulation of H2/air combustion using CFX. I could not get the expected temperature, the maximum flame temperature is always below 980K. I use stoichiometric mixture of hydrogen and air, but after the reaction, their always a lot of O2 left. It looks like a lean combustion. And the in the beginning of the simulation, CFX tell me
Reactants and products do not balance for a reaction.
| Products will not be scaled for conservation of mass. |
| Reaction : Hydrogen Oxygen |
| Products scale = 2.7750
My reaction chamber is a tube with 0.2 mm in diameter and 1.55mm in length, the inlet diameter is 0.1mm. Adiabatic wall condition.The boundary is the following:
Inlet: 300K, 6 m/s, Mass fraction H2: 0.02857 O2: 0.22857 N2: constraint,
Outlet: static pressure 1 bar
Initial temperature: 1000K
I use the default stoichiometric coefficient, so the reaction is H2 + 0.5 O2 = H2O,
Pre-Exponential Factor : 3.12e7 [m^1.5 s^-1 mol^-0.5] **(the value in Fluent is 9.87e8, I change the value since I have to switch the uint from "kmol" in Fluent to "mol" in CFX.)
Temperature Exponent : 0
Activation Energy : 3.1e+04 j/mol.
In the begining of the simulation, I use the time step of 1 e-7 s, then I increase the time step to 1 e-5 s.
Can you help me to diagnose the simulation? I appreciate for your help.
Last edited by xulixian; April 14, 2009 at 03:27.
|combustion, hydrogen, oxygen|
|Thread||Thread Starter||Forum||Replies||Last Post|
|Diesel combustion simulation ( Heat release rate)||venkatesh||CD-adapco||2||April 29, 2009 07:38|
|Scratch Space Error during combustion simulation||Emmanuel Kasseris||CD-adapco||10||October 25, 2008 17:12|
|simulation oil in combustion engine ?||Berg||FLUENT||0||April 23, 2006 09:25|
|about simulation of Pulverised coal combustion||kris||CD-adapco||0||September 1, 2005 04:50|
|timestep for combustion simulation||yangqing||FLUENT||0||August 18, 2002 08:46|