FWRP压力容器的可靠性设计研究

STUDY ON RELIABILITY DESIGN OF FILAMENT WOUND PRESSURE VESSEL

纤维缠绕聚合物基复合材料(FWRP)压力容器在航空航天及民用领域的应用是当前研究热点。减轻结构重量对于性能和成本都具有非常重要意义。为实现FWRP压力容器结构设计和安全评定的高目标,引入可靠性理论,应用统计学原理,基于应力-强度干涉模型,以同一失效概率为标准进行FWRP压力容器结构设计,以取代现应用的传统安全系数法设计。采用无碱无捻玻璃纤维-环氧树脂材料体系,应用同一缠绕工艺制备8个压力容器。试验得到纤维强度、缠绕角、几何尺寸、爆破压力等随机变量特征值。其结构可靠性设计值(纤维缠绕壁厚)与试验结果基本吻合,并显著小于常规设计值。将各设计变量随机分布特征值与压力容器结构设计相结合,实现安全与经济的有效统一,为可靠性设计在FWRP压力容器上的应用与发展提供了依据。

The application of filament wound pressure vessel in the aerospace and civil domain is becoming ahot point in the study nowadays. Reducing the structure weight is of much significance to its performance and costs.To meet the high requirement of structural design and safety evaluation for the pressure vessel, the traditional safetycoefficient design was substituted by the reliability design in its structural design with the application of the statisticalprinciple and the same failure probability, based on the stress-intensity interference model. Eight pressure vesselsare produced with the material system of E-glass roving and epoxy resin by the same winding technique. Experimental results includes all the probabilistic variables, such as the fiber strength, winding angle, geometric size, burststrength and so on. The value derived from the reliability design （ thickness of the winding fiber） is close to the experimental one and much smaller than that from the traditional design. The combination of theters of design variables with the structure design of the pressure vessel can realize the balance of safety and economyand provide the basis for the application and development of the reliability design in filament wound pressure vesselstructure design.