小型柔性接头推力矢量性能试验

设计了结构尺寸相同,弹性件材料分别为天然橡胶和硅橡胶的小型柔性接头,测试了容压作用下的轴向压缩位移,考察了弹性比力矩随温度(-50～70℃)、容压的变化情况.另外,为检验应力估算经验公式对小型柔性接头的适用性,测试了增强件内侧环向压缩应力.结果表明:柔性接头轴向压缩刚度随容压升高呈现一定程度的非线性增大趋势;弹性比力矩在0°～6°摆角范围内基本恒定,不同柔性接头弹性比力矩随容压升高呈现不同变化趋势;天然橡胶弹性件柔性接头弹性比力矩在低温下显著增大,硅橡胶弹性件柔性接头弹性比力矩在-50～70℃温区稳定;由燃烧室压强引起的增强件环向压缩应力经验公式估算值过大,不适用于小型柔性接头. 

Experimental investigation of miniature flexible joint thrust vector characteristics

Two miniature flexible joints which have the same structure but different elastomer materials (natural rubber and silicone rubber, respectively) were designed.Axial deflection variation due to vessel pressure was tested.Spring torque at various temperatures (-50～70℃) and vessel pressures were also studied.In addition, the reinforcement hoop compressive stress at the inner radius was measured to examine the applicability of existing empirical formulas for miniature flexible joints.Results show that the axial compressive stiffness increases slightly nonlinearly with the vessel pressure, while the spring rate keeps almost constant over the vector angle range from 0°to 6°.Spring rates of different flexible joints experience different variations as the vessel pressure increases.The temperature shows a pronounced effect on the spring rate.For the natural rubber elastomer flexible joint, the spring rate increases significantly at low temperatures.However in the silicone rubber elastomer case, the spring rate remains stable throughout the temperature range from -50℃ to 70℃.The stress empirical formula which would cause give much higher stress due to pressure is not applicable to the miniature flexible joint.