收缩-扩张喷管内气固两相流运动规律研究  

RESEARCH ON MOVEMENT LAW OF GAS-SOLID TWO-PHASE FLOW IN CONVERGENT-DIVERGENT NOZZLE

作　　者：李平 肖良华 何卫锋[1] 侯晓松 LI Ping;XIAO Liang-hua;HE Wei-feng;HOU Xiao-song(Aeronautics and Astronautics Engineering College,Airforce Engineering University,Xi＇an 710038,China;Beijing Aeronautical Technology Research Center,Beijing 100076,China)

机构地区：[1]空军工程大学航空航天工程学院,西安710038 [2]北京航空工程技术研究中心,北京100076

出　　处：《工程力学》2018年第12期240-247,共8页Engineering Mechanics

基　　金：国家自然科学基金项目(11602302);陕西省科技统筹创新工程计划项目(2015KTCQ01-72)

摘　　要：航空飞行器在简易跑道起飞或降落时,砂尘颗粒不可避免被发动机吸入,并与高速旋转的发动机叶片发生冲撞,导致叶片冲蚀损伤,显著降低发动机使用寿命,严重威胁飞行器的安全。试验中一般采用气动喷砂的方法将砂尘粒子加速至一定速度,并冲击试验件,以模拟发动机叶片的实际冲蚀过程。喷管是实现粒子加速的关键部件,该文通过试验和数值模拟对不同入口总压条件下收缩-扩张喷管加速砂尘颗粒的情况进行研究。实验中,通过压力传感器和双盘测速分别测量了喷管内壁静压和喷管出口处的颗粒速度;数值模拟中,采用实验入口总压条件,模拟了稀疏砂尘颗粒在喷管中的气固两相流运动,并详细分析了气流运动和颗粒的受力及加速情况。研究表明:数值模拟的气流压力分布及颗粒速度均与实验结果吻合;喷嘴出口处粒子速度随入口总压的增大而增大,且总压为0.23 MPa～0.4 MPa范围时的增长速率较大,而总压为0.4 MPa～0.56 MPa范围时的增长速率较小;粒子的加速主要发生在喷管的扩张段。Sand and dust particles will be inhaled by engine inevitably when the airplane takes off or lands on gravel ground. The particles collide with the engine blades. As a result the blades are eroded seriously, which shortens engine service time or even threatens the aircraft safety. To imitate the erosion process in laboratory, the blades or test specimens are fixed and impacted by high speed particles, which are accelerated by the pneumatic equipment. The air with high total pressure can expand to sonic or supersonic speed in a nozzle, and can be used to accelerate particles. So the nozzle is the key component to realize particle acceleration. The accelerations of air flow and sparse particles in a convergent-divergent nozzle with different total pressure were studied by experiments and numerical simulations. In the experiment, the wall pressure and particles velocity were measured by pressure sensor and Double Disc Method system, respectively. In the simulation, the gas-solid two phase flow was simulated. The results show that the pressure and particle velocity of simulation agrees well with the experimental results. The particle velocity at the nozzle exit increased with the total pressure, while the rate of increase for the total pressure at 0.23 MPa^0.4 MPa is larger than that at 0.4 MPa^0.56 MPa. The particle was accelerated mostly at the divergent part of the nozzle.

关 键 词：超音速喷管 颗粒速度 冲蚀 气固两相流 双盘测速 

分 类 号：V211.3[航空宇航科学与技术—航空宇航推进理论与工程]