In the continual effort to improve analysis and design techniques, Honeywell is investigating on the use of CFD to predict the aerodynamic performance of a high pressure turbine. The present study has a two fold objective. The first objective is to validate the commercially available CFD codes for aerodynamic performance prediction of a two-stage high pressure turbine at design and off-design points. The other objective is to establish guidelines to help the designer to successfully.set-up and execute the suitable CFD model analysis. The validation to model the stage interfaces is performed with three different types of approaches such as Mixing Plane approach, Frozen Rotor approach and NonLinear Harmonic approach. The film holes on the blade surface, hub and the shroud walls are modeled by using source term cooling and actual film hole modeling techniques for all the analysis. The validation is accomplished with the test results of a two-stage high pressure turbine, Energy Efficient Engine (E3). The aerodynamic performance data at a design point and typical off-design point are taken as test cases for the validation study. One dimensional performance parameters such as corrected mass flow rate, total pressure ratio, cycle efficiency along with two dimensional spanwise distribution of total pressure, total temperature which are obtained from CFD results are compared with test data. Flow field results are presented to understand the aerodynamic behavior.

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For combat aircraft design, the drag estimation plays a vital role for having better flight performance with less fuel consumption. The drag reduction has become a prime importance to military and civilian aircraft, because for an increase of one Count (i. e., CD=0.0001) necessitate for 80 kg reduction in weight for attaining the same performance. Therefore to persists a better performance of combat aircraft it is required an accurate prediction of drag at subsonic and supersonic speed. In supersonic speed, the drag becomes more essential due to shock wave formations which causes a wave drag. Computational Fluid Dynamics (CFD) techniques have been improved over the last decade for an accurate prediction of the drag at subsonic to supersonic speeds. The evaluation of drag assists in improving the aircraft design and performance. In this study, drag polar on combat aircraft with clean and stores configuration has been assessed for drag estimation. Initially, the study has been carried on body of revolution (BOR) to quantify the wave drag contribution between aircraft clean and stores configuration. Hence, BOR provides a rough estimation of drag for a given aircraft area-distribution in minimum turnaround time, as a consequence improving the aircraft design and performance through Aera-distribution. Moreover, the N-S simulation has been studied on 3D aircraft for drag polar from subsonic to supersonic speed. Results were shown that the estimated wave drag through BOR has shown similar to 3D Navier Stokes (NS) aircraft simulation. Further, the drag estimated at subsonic and supersonic regimes for clean and store configuration has shown that the drag was predominant at supersonic regimes due to the cause of wave drag than at subsonic regimes. Therefore minimizing the wave drag play an essential for combat aircraft performance. Several analytical [1, 2], experimental [3, 4] and numerical [5, 6] studies were made related to aerodynamic characteristics of fighter aircrafts for supersonic, transonic or subsonic regimes.