固体火箭发动机约束方式对内流场与结构共振影响数值研究  

Numerical study on effect of constraint mode on internalflow field and structure resonance of SRM

作　　者：王革[1] 周博成 杨铭义 蒲炜强 关奔 杨海威[1] 杨泽南 WANG Ge;ZHOU Bocheng;YANG Mingyi;PU Weiqiang;GUAN Ben;YANG Haiwei;YANG Zenan(Harbin Engineering University,Harbin 150001,China)

机构地区：[1]哈尔滨工程大学,哈尔滨150001

出　　处：《固体火箭技术》2023年第1期32-40,共9页Journal of Solid Rocket Technology

摘　　要：针对某型固体火箭发动机在地面试车时正常工作而在自由飞行试验中出现燃烧不稳定现象的问题,模拟地面试车和自由飞行条件发动机的外载荷,设计了近似等效的“强约束”和“弱约束”两种约束方式用于评估发动机的工作稳定性。使用ANSYS Workbench商业软件对发动机流场和结构进行建模,在两种结构约束方式下对发动机进行了模态分析与脉冲激励下的双向流固耦合计算。结果表明,不同的约束方式改变了结构的固有频率,可能导致结构振动频率与流场振荡频率一致而发生共振;发动机流场与结构的共振会提升内弹道压力振荡的振幅;模拟自由飞行条件的发动机可能发生流场与结构的共振,而模拟地面试车条件的发动机不会发生共振。Combustion instability occurs occasionally in the flight test of a solid rocket motor(SRM)even when it has passed the ground test.Imitating the external load of the SRM in the ground test and free flight conditions,two approximate equivalent constraints of“strong constraint”and“weak constraint”were used to evaluate the operating stability of SRM.The flow field and structure of SRM were modeled by using ANSYS Workbench software.The modal analysis and two-way fluid-solid coupling calculation for SRM under pulse excitation were carried out under two structural constraints.The results show that different constraint modes change the natural frequency of structure,which may lead to the resonance when the structural vibration frequency agree with the flow field oscillation frequency;the amplitude of the internal ballistic pressure oscillation can rise due to the resonance of flow field and structure of SRM;the resonance may occur in SRM modeled under the flight conditions,while the resonance does not occur in SRM modeled under the ground test conditions.

关 键 词：固体火箭发动机 燃烧不稳定 模态分析 双向流固耦合 

分 类 号：V435[航空宇航科学与技术—航空宇航推进理论与工程]