Avramenko A. The scientific basics of solving conjugate thermal gas dynamics problems when modelling a homogeneous process in a diesel engine

Thesis for a Doctor Degree of Technical Science, specialty 05.05.03. – “Engine and power plants” (14 – Electrical Engineering). – Kharkiv National Automobile and Highway University of the Ministry of Education and Science of Ukraine, Kharkiv, 2020. The dissertation deals with solving the problem of improving the fuel-and-economic, ecological and service life indicators of diesel engines by solving conjugate thermal gas dynamics problems with application of the advanced methodology of organising the operating cycle – Homogeneous Charge Compression Ignition (HCCI). During research, a complex of mathematical models was defined for solving conjugate thermal gas dynamics problems in the combustion chamber (CC) when simulating the thermally stressed state of CC parts with account of the process dynamics in the diesel engine cylinder. During research, the results of numerical modelling of motoring processes in diesel and HCCI engines (2F10,5/12 та 16FS26/27) were analysed. A method was developed for numerically modelling the following: the operating cycle of an HCCI engine with account of local fuel and air distribution in the cylinder; the specific features of ignition of the homogeneous air-fuel mix and the impact of thermomechanical deformation of CC parts on inner cylinder processes in diesel engines 2F10,5/12 and 16FS26/27. The impact of the specific features of the operating cycle of an HCCI engine on the level of the thermally stressed state of CC parts in diesel engines was investigated. The results obtained were used to work out research-based practical recommendations for improving the operating conditions of thermally stressed CC parts in diesel engines 2F10,5/12 and 16FS26/27. Key words: diesel engine, HCCI engine, associated problem of thermodynamics, heat transfer in ICE, head of cylinder, piston, ecological state, heat stressed state.