Calculation and Experimental Investigations of Local Heat Exchange at Piston Fire Bottom of Diesel Converted into Gas and Liquid Engine

Results are described of calculation and experimental investigations of local heat loads at pistons of the high-speed diesel and its modification converted into gas and liquid engine operating on the natural gas with an addition of a hot dose of the diesel fuel. The heat-stress state of pistons is investigated at basic operation regimes (nominal power and maximal torque). The comparative analysis of investigation results obtained for both engine variants has been performed with observing the identity of operation regime and construction of pistons (combustion chambers). It is established that the distribution of the temperature boundary condition over surfaces of fire bottoms of the investigated pistons are characterized with the substantial nonuniformity in both radial and circumferential directions. The diesel change-over to the gas and liquid regime has shown a decrease of temperature loads.