采用有限元软件,建立了某导弹固体火箭发动机模型,进行了发动机主动段(含推进剂)和被动段(不含推进剂)模态计算。计算结果表明发动机被动段模型与试验结果吻合较好,验证了计算方法可信度。对发动机主动段建模采用两种方法,一种方法忽略推进剂刚度,仅将其质量等效到发动机壳体上,另一种方法将推进剂进行实体建模。采用等效质量方法计算的发动机主动段的结果与试验结果误差稍大,采用将推进剂进行实体建模方法计算结果与试验结果一致性较好。

A solid rocket model of a missile is established by using finite element software. The modal calculations of the solid motor with and without propellant are carried out. The calculation results show that the motor passive model is in good agreement with the test results, and the reliability of the calculation method is verified. Two methods are used for modeling the active phase of the motor. One ignores the stiffness of the propellant and only equates its mass to the engine housing; the other is to conduct solid modeling of the propellant. There is a little error between the calculated results and the test results by using the equivalent mass method and the solid modeling method by using the propellant is in good agreement with the test results.