|
[Sponsors] |
March 1, 2018, 14:36 |
Two problems with setup of BVM and ECFM.
|
#1 |
New Member
Alex
Join Date: Jan 2018
Posts: 9
Rep Power: 9 |
Still experimenting with combustion of premixed mixture (propane+air from flamelet library) in closed volume ignited with spark.
The grid has been reworked with smaller elements, 7-layers inflation along the walls, a 30-deg sector with rotational symmetry has been used instead of a whole cylinder, which significantly accelerated the simulation. Mainly SST-model was used. There are two misunderstandings. 1. BVM shows similar results on different correlations. But with the increased pressure in the chamber - the reaction becomes slower. (For example, 3atm make flame 10% slower.) But this is not logical! The reaction should be accelerated at a higher pressure. I tried to prescribe higher reference pressure in CFX RIF, change the turbulence settings and the grid - this did not change the result. 2. ECFM normally worked on a coarse grid (the reaction was faster with increased pressure), but stopped working on a detailed one. The reaction extends some distance from the spark and is infinitely slowed down. Smaller first timesteps, increasing the power and volume of the spark - all this did not bring results. Perhaps I'm missing something too obvious. |
|
Thread Tools | Search this Thread |
Display Modes | |
|
|