Outer cylinder internal reinforcing ring structure optimization of mobile cryogenic liquefied natural gas storage tank

Maximum loading quality is one of the important directions of research and development of vehicle-mounted liquefied natural gas (LNG) tanks. According to the force condition in the actual operation of vehicle-mounted tanks,a novel fin sandwich structure reinforcing ring had been used to replace the original angle steel stiffening ring. Incorporated with genetic algorithm, the fin thickness,high wing,wing width,thickness and width on the lower of the sandwich structure had been optimized. Finite element analysis had been performed to analyze the effect of fin sandwich structure to the enhancement of the outer LNG storage tank cylinder under a variety of actual operation conditions and the stress conditions of overall and part of the tank. Results show that comparing with the angle steel stiffening ring, fin sandwich structure with the same height of reinforcing ring can ensure the safe operation of tank car, and the stress distribution on the outside cylinder is also more reasonable. In addition, by further changing the constraint condition, the modified type of reinforcing ring can be decreased to a height of 40 mm and the on-board LNG tanker loading volume can be increased to 1. 8 m³ under the condition of the safe operation of the tank car,which will greatly improve the operation efficiency and reduce the transportation cost.