turbulent round jet

jet · January 3, 2010, 20:27

Hi,
I have a question about the self-similarity profile of turbulent round jets.
If I compare the mean velocity profile in the self-similar round jet calculated with the k-epsilon-turbulence-model by OpenFOAM with experimental data from for example Hussein et al. I get a good agreement between the profiles except at the edge of the jet!
Is there any question to this behaviour?

Thank's for your help!

pg22 · February 10, 2010, 09:04

The standard k-epsilon model is not so accurate for the turbulent round jet. In particular, it tends to overpredict the spreading rate. This is often attributed to the epsilon equation and can be remedied by adjusting the model constants Ce1 and Ce2.

Alternatively, use the realizable k-epsilon model. This model correctly predicts the spreading rate of the round jet.

Paul.

skyinventorbt · March 5, 2012, 23:42

I am new to OpenFOAM, Kindly tell me the possible way to create mesh for round jet in a circular domain (Like pipe with sudden expansion, pipe being the nozzle & enlarged pipe being the flow domain) using BlockMesh. If anybody have done it, kindly help me...

January 3, 2010, 20:27	turbulent round jet	#1
jet New Member Join Date: Nov 2009 Posts: 12 Rep Power: 17	Hi, I have a question about the self-similarity profile of turbulent round jets. If I compare the mean velocity profile in the self-similar round jet calculated with the k-epsilon-turbulence-model by OpenFOAM with experimental data from for example Hussein et al. I get a good agreement between the profiles except at the edge of the jet! Is there any question to this behaviour? Thank's for your help!

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
CFD simulation of round turbulent jet	Sheeko	Main CFD Forum	4	June 18, 2013 21:53
Turbulent Round Jet	Obnates	FLUENT	8	May 14, 2009 10:55
Round jet model in FLUENT	PurdueME	Main CFD Forum	2	April 8, 2009 17:41
Turbulent Intensity good or bad for a jet	Christian	Main CFD Forum	0	November 19, 2003 06:47
Transient behaviour of a round jet	Clifford Arnold	Main CFD Forum	15	November 10, 1998 17:47

February 10, 2010, 09:04		#2
pg22 New Member Paul Garlick Join Date: Mar 2009 Location: Bournemouth, UK Posts: 27 Rep Power: 17	The standard k-epsilon model is not so accurate for the turbulent round jet. In particular, it tends to overpredict the spreading rate. This is often attributed to the epsilon equation and can be remedied by adjusting the model constants Ce1 and Ce2. Alternatively, use the realizable k-epsilon model. This model correctly predicts the spreading rate of the round jet. Paul.

March 5, 2012, 23:42		#3
skyinventorbt Member Dr. B T KANNAN Join Date: Jul 2011 Location: CHENNAI (MADRAS), INDIA Posts: 55 Rep Power: 15	I am new to OpenFOAM, Kindly tell me the possible way to create mesh for *round jet in a circular domain* (Like pipe with sudden expansion, pipe being the nozzle & enlarged pipe being the flow domain) using BlockMesh. If anybody have done it, kindly help me...