Improved Empirical Model for Base Drag Prediction on Missile Configurations Basedon New Wind Tunnel Data

摘要

New wind tunnel data have been taken, and a new empirical model has beendeveloped for predicting base drag on missile configurations. The new wind tunnel data were taken at NASA/LaRC in the Unitary Plan Wind Tunnel at Mach numbers from 2.0 to 4.5, angles of attack to 16 deg, fin control deflections up to 20 deg, fin thickness-to-chord (t/c) ratio of 0.05 to 0.15, and fin locations flush with the base to two chord lengths upstream of the base. The newly developed empirical model uses these data along with previous wind tunnel data. It estimates base drag as a function of all the above variables along with boattail and power-on or power-off effects. In comparing the new empirical model to that used in the former aeroprediction code, the new model gives improved accuracy over wind tunnel data. The new model also is more robust due to inclusion of additional variables. On the other hand, additional wind tunnel data are needed to validate or modify the current empirical model in areas where data are not available.... Empirical model, Missile configuration, Wind tunnel, Base drag prediction.