Evaluation of aerospike for drag reduction on a blunt nose using experimental and numerical modeling

The modification of high-speed flight vehicles by adding a spike attached to the stagnation point yields a complex flow-field full of interesting details. The purpose of this work is to contribute to the following two aspects. First, to analyze the interaction between oblique shock, separation shock and reattachment shock to explain the mechanism of drag reduction caused by the spike. Second, to assess the impact of varying the spike length (L/D = 0.5, 1.0 and 1.5), angle-of-attack (up to 10°) and Mach number (up to 3) on the level of drag reduction. The results reveal that, by comparing with the un-spiked blunt nose, the maximum drag reduction is 42% for L/D = 1.0 at α = 0°. For higher angles-of-attack, the spike is found to have little benefits in reducing the drag. Moreover, the efficiency of the spike in reducing drag and increasing lift depends largely on spike length. However, the spike length does not influence the aerodynamic coefficients when it exceeds the value of the blunt-body diameter ratio.