Determination of the thermal state of the elements of a piston engine turbocharger

Abstract

The power boost of heat engines is conditioned by the increase in the load on all its elements and related units. The turbocharger is one of the most common units that provide the power boost of a heat engine. The reliability of the turbocharger and its tribo-couplings guarantees the stable operation of not only it, but also the machine as a whole. An increase in the rotor speed leads to an increase in the thermal loading of the turbocharger elements. In this regard, timely assessment of the thermal state of the tribocoupling components, temperature distribution over the shaft, housing and other elements of the turbocharger is an urgent task. An algorithm for calculating heat transfer between the elements of a turbocharger has been developed, and an assessment of the heat load of radial multilayer plain bearings of a flexible asymmetric rotor has been made. The simulation was carried out in the ANSYS Fluent software package. The experimental data of the manufacturing plant were used as boundary conditions. The results of the calculation are given: the distribution of thermal fields in the turbocharger housing and the temperature in the area of ??the turbine and compressor plain bearings. Dependences of temperatures in the bearing area on the rotor speed are obtained. The calculation results were verified by comparing the temperatures in the turbine and compressor plain bearings with the data given in the publications of other authors. The temperature values in the outer and inner layers of the bearing were the initial data for calculating the dynamics of the turbocharger rotor, taking into account the thermal deformations of the tribocouple elements. The results of the research will be used to assess the stability of the movement of the rotor, the failure-free operation of the bearing assembly, as well as the reliability and durability of the turbocharger as a whole.