reg:Pressure dependencies with velocities
 

Hi ! I am doing 2d-flow past a cylinder (Unsteady-incompressible) Large Eddy simulations in fluent and try to capture the Pressure Fluctuations for 4 differnet velocities (dia,density, distance from the cylinder all are constant ) at a point located at the wake.

In regarding this , I would like to validate my meshes on the basis of Pressure fluctuations captured at my reciever location. In connection with that, I need some theoritical relations between Pressure and Velocity (and Dia and Distance also accounts)

In M.M.Zdravkovich , I have found that Average of the Fluctauting (P')2 is proportional to the fourth power of velocity. How can I fix a value of theoritical Pressure on the basis of Velocity????

Will be the following relation will be a valid one ... since my density is constant

(P ')2 = (RHO)2 * (V)4

If not, Please reply me , if anybody knows some thoeritical stuffs....

Re: reg:Pressure dependencies with velocities
 

I don't see why you need a modeled relation between pressure fluctuation and velocity. Doesn't your CFD solution include both pressure and velocity? Why not get the pressure fluctuation (and/or velocity) directly from the unsteady flow field?

Re: reg:Pressure dependencies with velocities
 

You may use the energy equation that energy will always be constant.

potential energy + pressure energy + kinetics energy = constant

z + P/pho.g + v^0.5/2.g = constant

if the z =constant, then the pressure is inverse proportional to the velocity.