高承压、低成本的车用35MPa玄武岩纤维缠绕复合材料气瓶

A preliminary design on 35 MPa cylinders made of basalt fiber wound composite for vehicles

为了提高压缩天然气(CNG)汽车的续驶里程,将CNG气瓶工作压力由20 MPa提高到35 MPa,同时采用高强度、低成本、储量丰富的新型缠绕纤维——玄武岩纤维来替代传统碳纤维和玻璃纤维,设计出车用35 MPa玄武岩纤维缠绕复合材料气瓶。通过薄膜理论和网格分析法计算出复合材料气瓶内衬和纤维缠绕层基本结构参数,利用ANSYS Workbench ACP模块建立1/2气瓶模型,数值模拟了气瓶在各种工况下的强度和稳定性。结果表明:(1)铝合金内衬在35 MPa工作压力下,最大应力位于封头和筒身的过渡段,其值为166.19 MPa,小于铝合金内衬屈服强度的60%即177.6 MPa;(2)环向缠绕层和螺旋缠绕层在爆破压力119 MPa下的最大应力分别为3 742.6 MPa和3 490.6 MPa,满足玄武岩增强纤维抗拉强度(3 000～4 840 MPa)的范围,符合DOT-CFFC铝合金内衬全缠绕复合材料气瓶的相关要求;(3)新型材料玄武岩纤维可以替代碳纤维和玻璃纤维缠绕在CNG气瓶上,能够满足气瓶的承压要求,安全可靠。结论认为,将目前常用的车用CNG气瓶工作压力由20 MPa提高到35 MPa可行,该研究成果有助于天然气汽车的应用推广。

In order to increase the driving range of compressed natural gas(CNG)vehicles,it was proposed to increase the working pressure of CNG cylinders from20MPa to35MPa in this paper.In addition,a35MPa cylinder made of basalt fiber wound composite for vehicles was designed by replacing the traditional carbon and glass fibers with a new type of winding fibers which has high strength,low cost and abundant reserves,i.e.the basalt fiber.Then,the basic structural parameters of composite cylinder lining and filament winding layer were calculated based on the film theory and by the grid analysis method.Finally,the1/2cylinder model was developed by using ANSYS Workbench ACP module,and the strength and stability of cylinder under different working conditions were numerically simulated.And the following research results were obtained.First,under the working pressure of35MPa,the maximum stress of aluminum alloy lining lies in the changeover portion between the end cap and the cylinder body.The value is166.19MPa,which is less than60%of the yield strength of aluminum alloy lining,i.e.177.6MPa.Second,under the blasting pressure of119MPa,the maximum stresses of the hoop-winding layer and the spiral-winding layer are3742.6MPa and3490.6MPa respectively,which meet the tensile strength range of basalt reinforced fiber(3000–4840MPa)and satisfy the relevant requirements of DOT-CFFC cylinders made of aluminum alloy lined full-winding composite.Third,this new type of basalt fiber can substitute carbon fiber and glass fiber to wind CNG cylinders,and it can satisfy the pressure requirement of gas cylinders,presenting safety and reliability.In conclusion,it is feasible to increase the working pressure of commonly used CNG cylinders from20MPa to35MPa.And the research results are conducive to the application and popularization of natural gas vehicles.