pressure development
Dear friends,
I was trying to simulate nonreacting flow characteristics in a simple can type gas turbine combustion chamber. The pressure contour showed that the pressure increased from inlet face to exit face. My question is what is the reason to increase in pressure. As the velocity increases, the pressure should decreases no? Please correct me if I am wrong. Thanks in advance. Prom 
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You made an assumption based on the Bernouilli relation but that applies for isoentropic, incompressible flows. Are you solving viscous flows? 
It is compressible model, the geometry is simple can type combustor solved for steady state, isothermal process. Air is used as fluid.

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Hi. Is that the static pressure? I think it makes sense since the flow is decelerated along the combustor. Flow is injected from a nozzle at very high speed and small section area. As the gas flows along a wider section it is decelerated (to conserve total mass flow rate) and therefore its static pressure is increased.
Did you try plotting the total pressure (static + dynamic). I guess you'll then obtain a decreasing profile along the combustor. Cheers, Michujo. 
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2) your model is compressible, therefore without density and velocity the pressure plot alone does not make sense 3) are you using also some turbulence modelling? because for compressible model it enters into the pressure 
yes I used kepsilon model

Yes it is static pressure plot... I am pretty convinced by Mr. Michujo's explanation. thank you sir. And I am new to CFX, I don't know how to plot the total pressure. BUt I'll give it a try...

Dear Filippo Maria Denaro,
Is it wrong if negative pressure comes. please explain it. kindly elaborate the concept of it. thank you... 
If you plot the thermodinamic pressure rho*R*T it must be always positive, if you plot the dynamic pressure rho*V^2 it must be positive, too.
Therefore, or you are plotting a scaled pressure or your results are wrong. In any case your plots say nothing if are not completed by other variables 
Dear Filippo,
In CFX post I used pressure which we get by clicking on pressure in contour ploting. I dont have knowledge whether it is thermodynamic or dynamic pressure. But if I plot total pressure, then also I get negative pressure. I have very little knowledge in this. Plz tell me where it has gone wrong. The total pressure is in this link: https://docs.google.com/file/d/0B9tq...it?usp=sharing Thank you 
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I am very sorry for my stupid questions sir. I am a beginner. Thanks for all your replies.

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