Enthalpy Diffusion Testcase

gregor · September 7, 2013, 08:15

Hi guys,

i am currently compiling a set of test cases to see if my solver derived from reactingFoam 2.0.x conserves specific properties. One test case that worries me a bit is the diffusion of a temperature profile. With all source terms switched off in the sensible enthalpy equation i am looking at the mean enthalpy of the gas in my domain. However with all tested solvers it seems that the enthalpy decreases over time. Maybe its just a boundary or set up problem or something that i am overlooking.

You can find the relevant files at:

https://github.com/greole/ValidationCases

Thanks alot

Gregor

adhiraj · September 8, 2013, 02:14

Do you account for enthakpy diffusion?
Try running the solver with Le=1. and see if that helps.

gregor · September 8, 2013, 10:46

Hi Adhiraj,

thx for your reply. I am running the test case with the reactingFoam solver which accounts for enthalpy diffusion. Le=1 didn't change anything (I use Y_N2=1 everywhere, anyway). What i find interesting is that if i solve for a passive scalar the mean value is conserved. Can someone confirm the behaviour of missing enthalpy or sees any problem with the test case ?

Gregor

September 7, 2013, 08:15	Enthalpy Diffusion Testcase	#1
gregor Member Gregor Olenik Join Date: Jun 2009 Location: http://greole.github.io/ Posts: 89 Rep Power: 18	Hi guys, i am currently compiling a set of test cases to see if my solver derived from reactingFoam 2.0.x conserves specific properties. One test case that worries me a bit is the diffusion of a temperature profile. With all source terms switched off in the sensible enthalpy equation i am looking at the mean enthalpy of the gas in my domain. However with all tested solvers it seems that the enthalpy decreases over time. Maybe its just a boundary or set up problem or something that i am overlooking. You can find the relevant files at: https://github.com/greole/ValidationCases Thanks alot Gregor

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Sensible Enthalpy vs. Total enthalpy	Sethi	OpenFOAM Programming & Development	3	March 23, 2017 22:48
Enthalpy source of Particle in DPM	icemesh	FLUENT	1	March 23, 2016 06:19
Moving mesh	Niklas Wikstrom (Wikstrom)	OpenFOAM Running, Solving & CFD	122	June 15, 2014 07:20
Enthalpy in a binary gas mixture	ChrisA	FLUENT	0	August 26, 2013 20:32
How to stop diffusion and advection in a zone for selected species.	hda	FLUENT	0	March 19, 2012 00:59

September 8, 2013, 02:14		#2
adhiraj Senior Member Adhiraj Join Date: Sep 2010 Location: Karnataka, India Posts: 187 Rep Power: 17	Do you account for enthakpy diffusion? Try running the solver with Le=1. and see if that helps.

September 8, 2013, 10:46		#3
gregor Member Gregor Olenik Join Date: Jun 2009 Location: http://greole.github.io/ Posts: 89 Rep Power: 18	Hi Adhiraj, thx for your reply. I am running the test case with the reactingFoam solver which accounts for enthalpy diffusion. Le=1 didn't change anything (I use Y_N2=1 everywhere, anyway). What i find interesting is that if i solve for a passive scalar the mean value is conserved. Can someone confirm the behaviour of missing enthalpy or sees any problem with the test case ? Gregor