超声速溢流条件下二元超声速进气道附加阻力计算

Calculation of additional drag coefficient of supersonic inlet under supersonic spillage condition

通过几何关系导出了单楔、双楔和三楔超声速进气道在零攻角及有攻角时的附加阻力系数计算公式,并进一步得出了N-1楔进气道的附加阻力系数计算通用公式.通过算例研究分析了飞行马赫数、飞行攻角及进气道总转角对附加阻力的影响.分析表明,进气道在超声速溢流条件下,附加阻力只同飞行马赫数、攻角及各楔面转角有关;附加阻力随飞行马赫数增加而减少,随攻角及进气道外压缩面总转角增大而增大;对于加速爬升用冲压发动机而言,设计时应注意减少附加阻力,并结合弹道、气动外形合理选择攻角.

The paper deduced the calculation formulae of the additional drag coefficient with or without attack angle in single wedge,double wedges and three wedges supersonic inlets by geometrical relationship.The general additional drag coefficient calculation formulae were further proposed.By studying the cases,the effect of flight Mach number,fight attack angle and total inlet corner on additional drag was investigated and analyzed.The analysis indicates that the additional drag is only related to flight Mach number,attack angle and each wedge surface corner under supercritical conditions.The additional drag decreases when flight Mach number increases,and increases when attach angle and total inlet corner increases.For the design of a ramjet for accelerating-climbing-used,more attention should be paid to reduce the additional drag.