Reynolds Number for Nozzle
I want to compute the reynolds number for a Nozzle. The information I have at nozzle exit conditions is
Mach number M=0.90, Velocity U=285 m/s, Total Temp. T0=290K, Diameter D=0.56 in, Lip thickness 0.03 in. Can anyone please help me in finding the Reynolds number... Can I just go by the Re based on diameter? I want to find the first grid point distance from the wall for the grid representing the flow inside the nozzle. Thanks, Shyam 
Re: Reynolds Number for Nozzle
Mr. Shyam Re=rho*U*D/Mu, So you need to know about properties of fluid i.e Mu. Assuming the flow in nozzle is quasi one dimensional calculate the Re using above expression.

Re: Reynolds Number for Nozzle
But, is it ok to assume the nozzle as quasi onedimensional nozzle? My doubt was, in case of turbulent boundary layers, is the Re calculation still applicable, or there are other forumulations?

Re: Reynolds Number for Nozzle
In order to assess whether you can assume a 1D flow, we need more info about the shape of the nozzle. Is it conical, fluted ??? Also, assuming your talking about calculating your y+ value, why would someone come up with a turbulent wall function for a laminar flow? The method you use to calculate y+ depends on the turbulence model you are using. Getting the right y+ value is often an iterative process anyway, so make an estimate based on Re, pull out what y+ is, and adjusted it until you get something sensible.

Re: Reynolds Number for Nozzle
In order to assess whether you can assume a 1D flow, we need more info about the shape of the nozzle. Is it conical, fluted ??? Also, assuming your talking about calculating your y+ value, why would someone come up with a turbulent wall function for a laminar flow? The method you use to calculate y+ depends on the turbulence model you are using. Getting the right y+ value is often an iterative process anyway, so make an estimate based on Re, pull out what y+ is, and adjusted it until you get something sensible.

All times are GMT 4. The time now is 22:54. 