Urgent: Role of Reynolds No in NS Equations
 

Hi, I am validating my 2D RANS code for RAE2822 airfoil. The input conditions are Mach # 0.734 AOA 2.54 Re 6.5e+6 I am not clear how to corelate the Reynolds no with my code as i have used the dimensional form and Reynolds no is not used anywhere. Is it to do something with viscosity (meu) setting as Re= rho*u*L/meu.... Meu i am taknig as per Sutherlands Law with temperature as only variable. Thanks NIDurrani

Re: Urgent: Role of Reynolds No in NS Equations
 

NIDurrani,

Your Re definition is correct. It is common to use the free stream state velocity, density, temperature (and hence viscosity) and the airfoil chord length as the characteristic dimensions. From these you may calculate Re in your case. Equivalently, if you non-dimensinalize your (dimensional) equations wrt to the above characteristic dimensions consistently, then Re (and also Ma and Pr) will naturally appear in the resulting non-dimensional eqautions. This is a simple and recommended excercise.