Modernization of the cooling system for diesel engines of the YAMZ family with the aim of reducing cavitation damages

The article deals with issues related to the modernization of diesel engines to reduce their cavitation damages. During the operation of diesel engines, local fractures can occur, as a rule, the causes of these disruptions can be the vibrations of the walls of cooling cavities of diesel engines, resulting in ruptures of the liquid, which leads to higher pressures, temperatures and potential differences in the cooling sphere. These factors have a destructive effect on the surface of parts, washed with coolant. To maintain a normal thermal regime, it is necessary to remove excess heat from heated parts, that is why the cooling system is designed. One of the promising trends in the development of this system is the increase in the average temperature of the cooling liquid in the water path of internal combustion engines above 100 ° C with a corresponding increase in pressure in the jacket space, which eliminates the boiling of water. As the temperature of the coolant rises, the fraction of heat carried away with the cooler decreases, and the period of self-ignition delay decreases, and the degree of increase in pressure during combustion decreases, which has a positive effect on the operation period of engine parts. Analyzing the reliability of the liquid circuit, it must be taken into account that the efficiency of the pump depends largely on the temperature of the coolant. At a coolant temperature close to the boiling point of the coolant, cavitation phenomena occur, which are manifested in a sharp drop in the productivity of the pump due to the appearance of air and steam bubbles in the liquid. It becomes difficult to ensure the non-cavitation operation of the water pump. Cavitation in the flowing part of the pump often leads to a violation of the circulation of coolant in the circuit and overheating of the diesel. The inclusion of a high-temperature cooling system in the water system of the mixing and supporting device parallel to the water pump is one of the simplest and most effective ways to increase the pump's available cavitation supply.

internal combustion engine, cooling system, modernization, cavitation failure, high-temperature cooling, pump