Features of complex calculation ejection cooling system charge air in diesel

The expediency of increasing the density of fresh charge at the inlet to the cylinder of a diesel engine with a gas turbine boost by using an ejection cooling system after the compressor to circulate cooling air through the cooler is substantiated. The urgency of improving the cooling systems of the charge air is noted in the direction of reducing the cost of power for operation and simplifying the design of their elements. The functional and design features of the elements of the charge air ejection cooling system are considered. The incompleteness of studying the functioning of the ejector at the outlet for intensive circulation of cooling air through the cooler matrix when placing the ejector after the turbocharger turbine is noted. The sequence of calculation of the system in the form of a block diagram is proposed, including a diesel engine, a compressor and a turbocharger turbine, a charge air cooler and an ejector in the exhaust system. The main factors characterizing the relationship between the functional and geometric parameters of the system elements are considered. The features of the complex calculation of the ejection cooling system for charge air in a diesel engine using mathematical modeling of processes in various elements of the system to find reserves and compromise solutions to reduce the cost of power for its operation and increase its efficiency are reflected. The results of the complex calculation of the ejection cooling system of the charge air using numerical modeling are presented graphically in the form of dependences of the parameters of its elements on the degree of pressure reduction in the turbocharger turbine. The analysis of the results of the complex calculation shows that the maximum values of the degree of cooling, charge air density and effective diesel power are achieved at different degrees of pressure reduction in the turbine or ejector. In this regard, it is concluded that it is advisable to choose the required values of the degrees of pressure reduction in the turbine or ejector on a compromise basis when designing an ejection cooling system for charge air.