Study on structure lightweight of the vehicle mounted LNG tank

LNG vehicle tank has been widely used in transportation industry due to its high efficiency and low cost. Researchers have proved that vehicle lightweight is one of the important objectives for the development of vehicle mounted LNG tanks. The lightweight of LNG tank structure plays an important role in the weight reduction of full vehicle, and great economic benefits can be brought through the introduction of lightweight. Structure optimization is one of the most common lightweight methods and structure lightweight design is a systematical project that is involved with crashworthiness, stiffness, Eigen mode and vibration, harshness performance. The surrogate based design optimization is considered as one of the efficient approaches to dealing with complicated engineering problems. 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. The fin thickness, height, width, thickness and thickness and width of upper and lower plates of the sandwich structure had been optimized using the genetic algorithm. 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 operating conditions and the stress conditions of overall and part of the tank. Results show that in comparison to the angle steel stiffening ring, fin sandwich structure with the same stiffness and strength of reinforcing ring can ensure the safe operation of tank car, and the stress distribution on the outside cylinder is also more reasonable. Through the adoption of this new type of reinforcing ring, great economic benefits can be brought which will greatly improve the operation efficiency and reduce the transportation cost.