Numerical calculation for the small thrust measurement system of Laval nozzle
LU Yonghua1, WEI Wenquan1, SHAO Feixiang2, SUN Yuxi3
(1.College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China; 2.CAMA LUOYANG GAS SUPPLY CO., LTD, Luoyang 471003, China; 3.CRRC QINGDAO SIFANG CO., LTD, Qingdao 266111, China)
 

Abstract: Aiming at the load surface location problem of the nozzle which was in the satellite attitude adjustment capsule, the fluid calculation software Fluent was used to simulate the Laval nozzle and its extensional flow field by adopting finite volume method, according to the baffle position and inlet total pressure. Furthermore, the effect of the baffle on the nozzle and its extensional flow field were analyzed. Three kinds of Laval nozzles of which outlet diameters were respectively 5.1, 3.6 and 2.3 were employed to make numerical calculation, and the size of their thrust were all within 10 N. The results indicate when the baffle is fixed, the baffle makes an influence on the outlet pressure of nozzles if nozzle Ⅰ, Ⅱ, Ⅲ of inlet and outlet pressure ratios respectively exceed 10, 12 and 15. When the inlet total pressure is constant, each type of nozzle has its corresponding location area of suitable placing the baffle, which is not the same with each other.
Key words: Laval nozzle; small thrust; baffle; the pressure ratio; numerical calculation