Inovatīvu risinājumu izstrāde iekšdedzes motoru gāzu apmaiņas sistēmas efektivitātes paaugstināšanai: promocijas darba kopsavilkums zinātnes doktora grāda (Ph.D.) iegūšanai | Innovative improvements of gas exchange system efficiency for internal combustion engines: Summary of the doctoral thesis for the doctoral degree of science (Ph.D.)

The aim of the thesis is to develop an improved throttle valve design, evaluate its effect on engine performance. As an innovative solution, a unique throttle valve design has been developed and patented, and a specialized power measurement device constructed, putting forward the following hypothesis – an improved throttle valve design for internal combustion engine develops a higher specific mass flow rate, ensuring more uniform operation and improved mixture preparation quality, compared to a butterfly type throttle valve design. To achieve this goal, the following tasks have been defined: (1) evaluation of the advantages and disadvantages of throttle valve analogues available in the world patent database; (2) describing the influence of gas dynamics in intake and exhaust system on engine performance; (3) identification of constructive parameters of gas exchange system components, their influence on gas dynamics, and obtaining mathematical data for experimental and design studies; (4) development and patenting of a digital prototype for a unique design throttle valve and power measurement device for testing motor vehicles equipped with such throttle valve; (5) determination of the effect of gas exchange system constructive changes on engine performance by experimental and design studies; (6) the approbation of the constructed power measurement device; (7) economic evaluation of the developed throttle valve prototype and constructed power measurement device. The analytical section examines the operating principles of gas exchange systems, including throttle valve, analogous devices available in the world patent database and their advantages and disadvantages are identified. The theoretical section describes the calculation principles of intake and exhaust system operational parameters and gas dynamics based on the motor vehicle available for experimental research. In the practical section, a digital prototype of a unique internal combustion engine throttle valve design has been developed and patented, adapted for use on the said motor vehicle. With the help of a grant from LBTU, a chassis-type dyno bench has been constructed, which contains a unique mechanical design, based on which a patent application of the Republic of Latvia has been submitted. In the experimental section, based on the output data obtained in the theoretical section, experimental and design studies of the developed digital prototype have been performed to evaluate its effect on engine performance, as well as the approbation of the constructed dyno bench. The manufacturing costs of the throttle valve prototype and the constructed dyno bench have been calculated and summarized, and the economic evaluation performed. The conclusions confirm the proposed hypothesis – the developed throttle valve design provides higher specific mass flow rate and improved fuel injection characteristics compared to the butterfly type throttle valve. The developed dyno bench provides measurement repeatability comparable to analogous systems available on the market.