表面凹凸药形固液火箭发动机燃速特性仿真研究  

Burning rate characteristics of hybrid rocket motor with a concave⁃convex grain

作　　者：魏小青 李悦龙 杨乾 WEI Xiaoqing;LI Yuelong;YANG Qian(The 41st Institute of the Fourth Academy of CASC,Xi'an710025,China)

机构地区：[1]中国航天科技集团有限公司四院四十一所,西安710025

出　　处：《固体火箭技术》2021年第6期757-766,共10页Journal of Solid Rocket Technology

摘　　要：为克服传统固液火箭发动机燃速低的缺点,研究了表面凹凸药形固液火箭发动机的燃速特性。选用气氧(Gase⁃ous Oxygen)/高密度聚乙烯(High Density Polyethylene)的推进剂组合,分析研究氧化剂流量、槽间距、槽宽、槽深等因素对燃速的影响。基于Navier⁃Stokes方程,建立了一种耦合湍流、化学反应、固体燃料热解和固⁃气界面边界条件的数值计算方法,并经算例验证该方法的正确性。应用该数值模拟方法,得到了固液火箭发动机的内流场的燃烧、流动特性,发现表面凹凸形药柱可以有效提高固液火箭发动机固体燃料药柱燃速;随着氧化剂流量增加,表面凹凸形药柱燃速增加,但增加幅度逐渐减小;槽间距增加,表面凹凸形药柱的平均燃速通常增加,但最终逼近相同氧化剂流量条件下传统药柱的平均燃速;槽宽增加,药柱的平均燃速减小;槽深对燃速影响较大,且随着槽深增加,药柱平均燃速降低。In order to overcome the low burning rate of traditional hybrid rocket motors,the burning rate characteristics of hy⁃brid rocket motor with a concave⁃convex grain were studied.The gaseous oxygen and high density polyethylene composite propellant was used,and the effects of oxidant flow rate,groove spacing,groove width and groove depth on the burning rate were investigated.Based on the Navier⁃Stokes equations,a numerical simulation method with coupled boundary conditions of turbulence,chemical re⁃actions,solid fuel pyrolysis and solid⁃gas interfacial was proposed,which was further proved by an example.Subsequently,the combustion and flow characteristics of the internal flow field in hybrid rocket motors were obtained.The numerical simulation results show that burning rate of the concave⁃convex propellant can be effectively improved.The burning rate of the concave⁃convex propel⁃lant increases with the increase of oxidant flow rate,but the increasing extent decreases gradually.With the increase of groove spac⁃ing,the average burning rate of concave⁃convex grain increases,but finally approximates to the average value of traditional grains under the same oxidant flow rate condtions.The average burning rate of concave⁃convex grain decreases with the increase of groove spacing.The burning rate is significantly influenced by the groove depth.Furthermore,the average burning rate decreases with the increase of groove depth.

关 键 词：固液火箭发动机 凹凸药形 燃速特性 

分 类 号：V438[航空宇航科学与技术—航空宇航推进理论与工程]