Determination of Base Pressure for the Agard-B Calibration Model and Comparision with an Experiment in the T-38 Wind Tunnel

 

Ali Akgül

Jovan Isaković

Slobodan Mandić

Emrah Gülay

 

The results of the base pressure measurements of the AGARD-B calibration model in the T-38 blowdown wind tunnel of the Military Technical Institute Serbia are given in this article. There is very good agreement between the measured base pressures in the MTI T-38 blowdown wind tunnel and the appropriate measured values in the IAR (NAE) 5ft trisonic wind tunnel (Canada). Also Computational Fluid Dynamics (CFD) calculations have been performed to predict base pressure values and the results are compared against both wind tunnel test results. The influence of the sting on the calculated values of the base pressures is established. The measured base pressures are between the calculated values for the CFD model alone and the CFD model with sting. The base pressures are also calculated by the semi-empirical method, MTI-DMAC at zero angle of attack and the USAF Missile DATCOM as a function of the angles of attack. The differences between the calculated and the measured base pressure can be related to the influence of the sting.

Key words: experimental aerodynamics, fluid dynamics, numerical simulation, base pressure, pressure coefficient.