Optimization of the reinforcing layer of the compressor wheel from the composite material of the diesel turbocharger

Abstract

The purpose of this paper is to search for the optimal configuration of the variable parameters of the reinforcing layer of a compressor wheel made of a composite material. The composite material considered in this paper is a carbon matrix filled with carbon fiber. Variable parameters were the fiber fraction in the composite, the total thickness of the reinforcing layer, and the fiber fraction in the composite oriented in the circumferential direction of the disk. The objective function in this study is the safety factor of the wheel. The parameters were optimized by the Gauss-Seidel method. At each optimization step, the problem of the theory of thermoelasticity of anisotropic media was solved by the finite element method. In the course of the study it was found that the maximum safety factor of the wheel 1,15 is achieved with the maximum fiber fraction in the composite, the thickness of the reinforcing layer 1,4 mm and the fiber fraction 0,581 oriented in the circumferential direction. The deformations of the wheel with the above parameters remain at an acceptable level. According to the results of calculations it is established that it is possible to increase the level of manufacturability of the impeller production due to the transition to the reinforcement of the disk only in the circumferential direction. At the same time, the reduction of the general safety factor will be less than 6 %. Proceeding from the results obtained during the optimization process, it follows that in the future the optimization problem for the component base considered in the work can be carried out only with respect to the fiber fraction oriented in the circumferential direction. In the final part of the work, an analysis of the mass-inertial characteristics of a composite wheel with a wheel produced using traditional technology was made. The mass and moment of inertia of the rotor in the case of a wheel from composite material will be reduced by 11 % and 18 %, respectively.