轴向过载下三维药柱热粘弹性有限元分析

基于药柱的三维线性热粘弹性积分本构关系,采用有限元法,对固体火箭推进剂药柱进行热粘弹性有限元分析,得出药柱在轴向过载作用下的变形结果和药柱内危险部位的位置,表明药柱具有明显的粘弹性特点。研究了在轴向过载条件下药柱和绝热层接触面之间的应力应变分布随泊松比变化的关系。分析表明,在泊松比增大的情况下,药柱应力也会随之增大,尤其是泊松比接近0.5时,药柱应力增大更加显著。

Study on thermo -viscoelasticity of solid propulsive agent column under axial overloading with FEM

Based on the three dimensional viscoelastic integral constitutive relation of a propellant grain with the finite element method (FEM), the analysis about the thermo-viscoelasticity of solid propulsive agent column is presented. The transmutation and the dangerous part of the propellant grain under the axial overloading is given; at the same time, the propellant grain has a viscoelastic characteristic.Under the axial overloading, the relation of the stress distributing between the column and thermal insulation layer with the change of Poisson's ratio is derived,. The results show that the stress about the column increases with the increasing of Poisson's ratio. Especially when the Poisson's ration is close to 0.5, the stress of the column will be evidently increases.