Mechanical stress design of a highly loaded radial inflow turbine for compact CHP turbine

The main objective of the current paper is to establish an optimal configuration for a micro gas turbine, component of a combined heat and power (CHP) system. The design and modeling of the turbine rotor were achieved using CAE/CAD software. This paper will focus mainly on identifying issues regarding the mechanical resistance of the radial turbine. In order to increase the safety factor, a brief analysis of the designing mechanical stages was necessary. The CAD model for the optimal impeller was realized considering the facilitation of its manufacturing process and maintenance. The analysis is based on finite element method, implemented in NASTRAN. The characteristics of the material used are the following: density 8180 kg/m3, 1.67E11 N/m2 and υ = 0.28, for an angular velocity of 40 000 rpm. The presented paper aims to determine a functional configuration for gas turbine’s impellers, in order to effectively manage to deal with the conditions of temperature and mechanical stresses resulted in the exploitation of a CHP gas turbine. This objective was achieved after iteratively designing multiple configurations.