复合材料压力容器的概率与区间可靠性设计

Probabilistic and interval reliability design of the composite pressure vessel

考虑复合材料压力容器结构中各参数和载荷的随机性或区间性,建立了该类压力容器的可靠性分析模型.应用随机因子法导出了纤维应力的均值、标准差的计算表达式,分别利用概率可靠性方法与区间可靠性方法并结合改进粒子群优化区间优化算法,实现了容器的概率可靠性设计与区间可靠性设计.最后考查了结构各不确定性参数的波动对容器厚度设计尺寸的影响.算例结果表明:概率和区间可靠性设计结果均可满足安全要求,且比传统的安全系数法结果更合理;概率方法相对区间方法,其结果取值范围较小,但计算过程复杂.

Considering the randomness or interval character of physical parameters and applied loads of composite pressure vessels （COPV）, the COPV reliability-analyzing model is built. And then the computational expressions for the mean value, standard deviation and deviation of fiber stress are deduced by the random factor method. The probabilistic and interval reliability designs on COPV are implemented by utilizing the probabilistic method and interval method combined with the improved particle swarm optimization （PSO） algorithm, respectively. The influence of fluctuation of structure uncertain parameters on COPV design thickness is inspected. Finally, examples are given to demonstrate that both probabilistie and interval reliability methods can satisfy the safety requirement and both are of higher rationality than the traditional safety factor method. And probabilistic method has a lower relative error but a higher computational complexity contrasted with the interval method.