[zwop]

Hello,

I am trying to replicate the results given in NASA's TMR 2D zero pressure gradient flat plate case (https://turbmodels.larc.nasa.gov/flatplate_val.html) in Fluent, but the skin friction coefficient plot across the surface I get is way off. I have tried my best to set the flow domain up to replicate the problem specifications, but I think I have some misconceptions regarding flow physics and setting up the problem so any direction would be very much appreciated! Thank you in advance!

I am using the finest 2D mesh downloaded from the database, with an average minimum y+ of 0.01. I am running the case as compressible even though it is firmly subsonic (M=0.2). The viscosity of air under material properties is set to 1.6148e-5 to get the desired Re of 5e6. The BCs are shown in the attached picture 'flatplatebc.jpg', and are set up to replicate the following conditions from TMR. Those that I have chosen seemed to be the most appropriate after reading the Fluent User guide.



The total/stagnation temperature and pressure conditions were calculated from isentropic equations, taking reference temperature to be 300K as given and pressure to be 101325Pa (assumed). This gives me a value of P=104190Pa and T=302.4K for the inlet, and P=101325Pa for the outlet. I checked to see that these indeed give the expected Pt/P_ref and P/Pref values, but I may have misunderstood the ratios? I took them to be total pressure over reference pressure, and static pressure over reference pressure respectively. However I checked the github for how SU2 set up the problem (https://github.com/su2code/VandV/blo...atplate_sa.cfg) and found that they used P=117691.7874Pa for inlet pressure and P=114455.0Pa for outlet. I am unsure of how these values were obtained, but if I run the study using their values of pressure I get a much more sensible velocity profile (see 'velocityprofile_su2bcs.jpg' and 'velocityprofile_mybcs.jpg' for a comparison).

However, there must also be something wrong with how I set up the problem in the first place as running the simulation to convergence with these BCs do not give me the expected skin friction coefficient values, I am getting c_f that start on the order of 1e-2 while its supposed to be on the order of 1e-3 as seen from this picture from SU2's verification study. (https://su2code.github.io/vandv_file...profile_sa.png)

Once again, thank you very much in advance for any help and direction, it is greatly appreciated!