CFD Online Discussion Forums

CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)
-   FLUENT (https://www.cfd-online.com/Forums/fluent/)
-   -   re:compressible fluid flow (https://www.cfd-online.com/Forums/fluent/42942-re-compressible-fluid-flow.html)

satya November 26, 2006 23:11

re:compressible fluid flow
 
hi im trying to model compressible fluid flow, from nozzle exhaust. i want to calculate temperature distribution of the exhaust plume at some depth. the exhaust plume is going to the deflector, so the temperature distribution at a point on deflector is to be calculated.i want to first model in 2-d . can any body give me idea how to proceeed? bye satya

mallesh November 28, 2006 03:17

Re: re:compressible fluid flow
 
first read some good books on compressible fluid flow (gas dynamics by ANDERSON.) you need to know the shock properties. you need to know whether it is a axisymetric case or 3d geometry. what are properites of gas that is coming out of the nozzle? what is the mach number at the exit of the nozzle?. do you want steady state case or unsteady state case? if unsteady, what is the tie duration?

what is the mass flow rate from the nozzle?

is the nozzle confined in space or free to atmosphere? boundary conditions>>>>>>>>>> give nozzle inlet: mass flow rate

nozzle exit : interior

deflector : wall

open atmosphere: pressure outlet


satya November 28, 2006 04:11

Re: re:compressible fluid flow
 
hi mallesh i know all the properties at exit of the nozzle,i,e mach number at exit, molecular weight of exhaust gases at exit of nozzle, sphecific heat of gases at nozzle exit, density of gases at nozzle exit. first of all i want to do steady state 2-d analysis first of all i want to tell u one thing, there is a gap between the nozzle exit and jet deflector of 3.5 m, so can it be approximated as that there is no gap between the nozzle exit and jet deflector and give the inlet properties of the jet deflector inlet as nozzle exit properties.


mallesh November 29, 2006 02:29

Re: re:compressible fluid flow
 
no, you should not assume that there is no gap between the nozzle and jet deflector. keep the gap so that you can see flow reflections fro the jet deflector. give mesh to entire nozzle, gap between nozzle and jet deflector and surronding atmosphere.

do not give nozzle exit properties as the input. you will miss some properties in the nozzle flow. so, include entire nozzle in the mesh domain. give input B.C at the nozzle inlet.

satya November 29, 2006 23:30

Re: re:compressible fluid flow
 
ok, for suppose if we consider that x,y,z are three deimensions of a co-ordinate system and in x- direction we will give dimension for the width and y as the depth of deflector and z as the nozzle axis. i tried to draw the drawing, then the deflector is axi-symmetric with the x-y plane ( width and depth) and eccentric in the the y-z plane (nozzle axis and depth plane) because the profile of the deflector is curved. so if i want to model in 2-d axi-symmetric model of the deflector can i make using the x-y plane.



All times are GMT -4. The time now is 07:34.