Jet flows with srtong shocks

November 22, 2002, 02:57

Hi,

Does any one have any experiance with modelling underexpanded supersonic (axisymmetric) jets which have mach disks present in them. I am using a 5 degree wedge (for the domain) to model the axisymmetric nature of the jet and the transient run dies with errors of negative densities as the mach stem is being formed in the jet flow field. Any help to alleviate this probelm is most appreciated.

regards N Menon

tejaswini16 · June 30, 2017, 18:06

Were you able to solve the problem?
I am modelling overexpanded flow and I am facing issues as well because of the shocks
Thanks!

JBeilke · December 26, 2017, 12:14

We completed the Ladenburg testcase (https://www.researchgate.net/profile...ication_detail ) successfully using ccm+.

There are some important details:

use laminar or k-Omega flow : never ever k-epsllon
use Courant number not smaller than 1
avoid running it steady state, it takes ages to converge

It works with transient Simple, PISO and also the coupled solver.

November 22, 2002, 02:57	Jet flows with srtong shocks	#1
nandu Guest Posts: n/a	Hi, Does any one have any experiance with modelling underexpanded supersonic (axisymmetric) jets which have mach disks present in them. I am using a 5 degree wedge (for the domain) to model the axisymmetric nature of the jet and the transient run dies with errors of negative densities as the mach stem is being formed in the jet flow field. Any help to alleviate this probelm is most appreciated. regards N Menon

June 30, 2017, 18:06	Similar issue	#2
tejaswini16 New Member Tejaswini Gautham Join Date: Jun 2017 Posts: 2 Rep Power: 0	Were you able to solve the problem? I am modelling overexpanded flow and I am facing issues as well because of the shocks Thanks!

December 26, 2017, 12:14		#3
JBeilke Senior Member Joern Beilke Join Date: Mar 2009 Location: Dresden Posts: 516 Rep Power: 20	We completed the Ladenburg testcase (https://www.researchgate.net/profile...ication_detail ) successfully using ccm+. There are some important details: use laminar or k-Omega flow : never ever k-epsllon use Courant number not smaller than 1 avoid running it steady state, it takes ages to converge It works with transient Simple, PISO and also the coupled solver.

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