# CFD simulation of rocket nozzle

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February 11, 2018, 07:29
CFD simulation of rocket nozzle
#1
Member

MIDHUN
Join Date: Nov 2012
Location: calicut
Posts: 45
Rep Power: 13
I am simulating a rocket nozzle with one inlet and four outlet with symmetric option .
I am given an inlet mass flow rate of 2.6 kg/s and temperature of 1500k but no outlet conditions .

1) should I give pressure outlet condition at the outlet by only creating the rocket nozzle or create a large atmospheric domain ? then what should be the boundary condition at outlet ?

2) should i give inflation in meshing ? i had used tetra unstructured mesh .

3 ) what is the most appropriate turbulence model , wall treatment and wall y plus value ?

4) can i specify mass flow inlet for this case ?

5) what is supersonic initial gauge pressure( in fluent mass flow inlet condition) and how can i calculate it ?
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 February 14, 2018, 01:44 #2 Senior Member   Shamoon Jamshed Join Date: Apr 2009 Location: Karachi Posts: 377 Rep Power: 17 1) should I give pressure outlet condition at the outlet by only creating the rocket nozzle or create a large atmospheric domain ? then what should be the boundary condition at outlet ? A1 . Pressure outlet can be given, but outflow will be much better; specify 0.25 for complete one and o.125 for the two half modeled. See your results and I think no need to model atmospheric domain. 2) should i give inflation in meshing ? i had used tetra unstructured mesh . Yes inflation is important 3 ) what is the most appropriate turbulence model , wall treatment and wall y plus value ? y+ should be should be 1 at any cost. if you use k-eps real then enhnced wall treatment is required or you can use k-w SST 4) can i specify mass flow inlet for this case ? yes 5) what is supersonic initial gauge pressure( in fluent mass flow inlet condition) and how can i calculate it ? S/S initial gauge press should be a hundred few pascals less than the total inlet pressure.

 Tags nozzle, rocket, supersonic flows