CAJ | 학술논문

对一二元收扩激波诱导矢量喷管进行了二维动态数值模拟，研究了不同落压比、不同次流加速时间下，喷管气动特性和流场结构随次流增加的变化规律。结果表明：喷管在过膨胀状态下，次流流量达到一定值时，其推力会有较强的振荡；在完全膨胀和欠膨胀状态下，振荡较小。其原因是，次流增加过程中，喷管出口附近有复杂波系存在和回流产生，而回流对提高推力和增加矢量角有益。
대일이원수확격파유도시량분관진행료이유동태수치모의，연구료불동락압비、불동차류가속시간하，분관기동특성화류장결구수차류증가적변화규률。결과표명：분관재과팽창상태하，차류류량체도일정치시，기추력회유교강적진탕；재완전팽창화흠팽창상태하，진탕교소。기원인시，차류증가과정중，분관출구부근유복잡파계존재화회유산생，이회류대제고추력화증가시량각유익。
2D dynamic numerical simulation of a shock vector controlled 2D-CD exhaust nozzle was con-ducted to investigate the effect of increasing secondary mass flow on the internal nozzle performance and flow field structure under different nozzle pressure ratios. Results indicate that when the secondary mass reaches a certain value, the thrust of nozzle will undergo a strong oscillation when nozzle is under over-ex-panded condition. The oscillation will be much weaker when nozzle is under either fully expanded or un-der-expanded conditions. This phenomenon is attributed to a series of complex waves near the nozzle outlet and the emergence of back flow. It is also concluded that back flow can enhance the performance of nozzle and enlarge the vector angle.