OPTIMIZATION OF PISTON BOWL GEOMETRY AND FUEL INJECTION PARAMETERS IN MODERN DIESEL ENGINES

This article investigates the influence of piston bowl geometry, injector nozzle design, spray direction, and in-cylinder air motion on the combustion quality of modern diesel engines. Unlike general studies that describe the combustion process in diesel engines, this paper focuses on design-related factors that improve air-fuel mixing, reduce incomplete combustion, and increase thermal efficiency. The study analyzes the role of re-entrant piston bowls, swirl and squish flows, multi-hole injectors, high-pressure fuel injection, and optimized spray targeting. The results show that the proper coordination of combustion chamber geometry and fuel injection parameters can improve mixture formation, increase combustion stability, reduce fuel consumption, and decrease harmful emissions such as soot, carbon monoxide, unburned hydrocarbons, and nitrogen oxides. The article concludes that the constructive improvement of combustion chamber and injection system elements is one of the most effective directions for increasing the efficiency and ecological performance of diesel engines.