CFD Online Logo CFD Online URL
Home > Forums > Software User Forums > Siemens

High pressure on combustion chamber; high temperature residuals

Register Blogs Members List Search Today's Posts Mark Forums Read

LinkBack Thread Tools Search this Thread Display Modes
Old   January 13, 2017, 10:34
Default High pressure on combustion chamber; high temperature residuals
New Member
Join Date: Nov 2016
Posts: 6
Rep Power: 5
cheet is on a distinguished road
I am simulating combustion processes of heptane/octane inside a rapid compression machine (batch compression, pressure driven, no valves, no spark). I am using ccm+ for geometry, ice for trimming (sector model) and combustion setup and prostar for solver setup and postprocessing. I am currently facing two issues:

1) I can observe combustion only by using the ECFM-3D model. The compression stroke is ok (deviation ~10% to experiments) but the extra pressure generated by combustion is way too high (experiment: +5bar, simulation: ~+100bar). Timescale is set adequately. There may be an issue with the state of premixing, as we do not exactly know about that inside our machine. If I use the PVM-MF model (mixed, non-prem., hcci), I cannot observe combustion at all, even if I set harsher boundary conditions.

2) Regardless of my settings, the temperature residues are very large. Close to lower dead point, they start accumulating (~0.002) and grow up to a value of 30 .. 500 at upper dead point.

Thanks in advance for your support.
Greets, Bernhard
cheet is offline   Reply With Quote


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
problem whit set a high region temperature for start combustion ca3tiel FLUENT 0 May 22, 2016 08:26
Calculation of the Governing Equations Mihail CFX 7 September 7, 2014 06:27
High Pressure Residuals ArathoN OpenFOAM Running, Solving & CFD 2 May 4, 2014 09:23
how to replace a shock tube high pressure port by a boundary condition? immortality OpenFOAM Pre-Processing 0 May 2, 2013 13:43
High pressure turbulent combustion Ralf Main CFD Forum 3 April 20, 2006 22:03

All times are GMT -4. The time now is 02:20.