View Issue Details
|ID||Project||Category||View Status||Date Submitted||Last Update|
|0000066||OpenFOAM||[All Projects] Bug||public||2010-10-26 08:16||2010-10-26 17:08|
|Fixed in Version|
|Summary||0000066: Temperature increases beyond inlet temperatures with reactions off|
|Description||Solved for only species transport, the CounterflowFlame2D tutorial file (in version 1.7.1) using reactingFoam.|
Specified reactions off and turbulent reactions off in constant/chemistryProperties.
Temperatures at both inlets are 800K (as was given in the tutorial file). No other modificattion in the files.
As no reactions, one would expect temperatures to be below 800K as only species transport.
However, the temperature increased beyond 800 K (it went close to 840 K - log file is attached).
Why temperatures should increase if there is no heat generation due to reaction?
|Tags||No tags attached.|
log.rar (315,096 bytes)
Our reactingFoam algorithm is an efficient, approximate method for turbulent reacting flow. However, in the laminar limit the approximation breaks down, leading to temperature inconsistencies.
In the laminar case, if you have a composition gradient, the only way to ensure that the diffusion does not give rise to temperature errors is by enforcing a Lewis no = 1 constraint, e.g. update the sensible enthalpy eqn to:
+ mvConvection->fvmDiv(phi, hs)
// - fvm::laplacian(turbulence->alphaEff(), hs)
- fvm::laplacian(turbulence->muEff(), hs) // unit lewis no.
This is an area that we would like to research and update in the future if we gain sponsorship to do so.
||File Added: log.rar|
||Priority||urgent => normal|
||Assigned To||=> user2|
||Status||new => assigned|
||Note Added: 0000094|
||Status||assigned => resolved|
||Resolution||open => suspended|