To obtain the best geometric size of VL sealing ring and improve its sealing performance, this paper carried out multi-objective optimization research on VL sealing ring by Isight software. Firstly, according to the working principle and geometric size of the VL seal ring, determined the constraint conditions, established the optimization objective equation, and given the value range of the structural parameters was. Then, verified the validity of the approximate model by fitting the radial basis neural network model provided. Finally, analyzed the sensitivity of influencing factors of oil film thickness at lip, and established the optimization module by NSGA-II multi-objective optimization algorithm. As a result, the best geometric size is obtained from multi-objective optimization, and the structure of VL seal ring has achieved the goal of more suitable high speed dynamic seal and longer service life.

No abstract

The aim of this work was to study the anti-penetration effect of sandwich composite armor with ceramic honeycomb structures filled with aluminum alloy under the impact of high-speed projectiles. The finite element software ABAQUS was used to conduct numerical simulation research on the process of a standard 12.7-mm projectile penetrating sandwich composite armor. The armor-piercing projectile model was simplified as a rigid body. The numerical simulation models were applied to three different sandwich composite armor structures (A, B, and C), each with a total armor thickness of 25 mm. The penetration resistance of the three kinds of composite armor was studied. We obtained velocity curves for the rigid projectile penetrating the different structures. The failure forms and penetration resistance characteristics of the three composite armor structures adopted in this paper were analyzed. In addition, the velocity reduction ratio is proposed as an index to evaluate the penetration resistance performance of the armor. The simulation results revealed decreasing rates of projectile speed in the structures A, B, and C of 69.6%, 91.1%, and 100%, respectively. The third composite armor (structure C) designed here has excellent penetration resistance and can block the penetration of a high-speed (818m/s) rigid projectile. This study can provide some reference for the application of laminated armor material in anti-penetration protection structures.

No abstract