Bluntness for Quasi-waverider and Its Effect on Performance

Abstract

For developing the hypersonic vehicle with high lift-to-drag performance, the design based on waverider is an effective approach. Because of the limit of aerodynamic heating, the sharp leading of hypersonic vehicle needs to be blunted in practical applications. Considering the advantages and disadvantages of waverider comprehensively, a kind of quasi-waverider hypersonic vehicle body is designed and a kind of bluntness method is carried out. According to the characteristics of the quasi-waverider, the leading edge and the sharp side edge are blunted, respectively. A method of increasing material was used to blunt the leading edge, of which the blunt curve is a circular curve. A blunt method for increasing material based on cubic Bezier curve is proposed for the sharp side edges. At the basis, the sharp side edges of top and bottom are blunted simultaneously, which not only ensuring a continuous smooth side surface, but also increasing volume of the quasi-waverider. The effect of bluntness on the aerodynamic force and aerodynamic heating of the configuration is studied by numerical simulation. Numerical calculation results show that aerodynamic force is influenced less by bluntness, while aerodynamic heating is influenced greater. The lift-drag ratio reduced about 11% due to blunt leading edge, while maximum heat flux decrease about 59% and aerodynamic heating performance is improved. The reason for the loss of the aerodynamic force is the bow shock wave produced by bluntness, resulting in the high pressure airflow of lower surface leaks to upper surface and lift coefficient reduce. The shock drag of edge increases greatly due to bluntness, causing drag coefficient increase. Investigation shows that the aerodynamic force and aerodynamic heating performance of quasi-waverider hypersonic aircraft are well balanced under this blunt method and the method can be used for the configuration design of hypersonic vehicle.