Investigation of heat release in a diesel engine when operating on gas fuel

Abstract

A study aimed at organizing the combustion process, which ensures the operation of a tractor diesel engine with external mixture formation, is relevant. The main purpose of the work is to determine the type and proportion of gas fuel added to the tractor diesel cylinders with a fresh charge, at which the mixture formation changes from internal to external. To determine the reliability of theoretical assumptions, experimental studies of a diesel engine with a dimension of 4CHN 11.0/12.5, brand D-245.5S2 were carried out on a load electric brake stand Rapido (made in Germany) brand SAK N670 with a balancing pendulum machine with a power of 250 kW, using specialized equipment for indexing. As a result, the change in mixture formation in the tractor diesel cylinders from internal to external, occurring at a constant diesel fuel injection rate, was theoretically substantiated. The type of gas fuel in the form of a propane-butane mixture with its addition to the main diesel fuel in an amount of 38 % and more by weight was determined as a gas fuel for the tractor diesel under consideration at a given load-speed mode of operation. It was experimentally established that the addition of a share of gas fuel up to 40 % led to the complete exclusion of the diffusion phase of the combustion process, which in turn indicated the transition of the operation of a diesel engine with a dimension of 4ChN 11.0 / 12.5, brand D-245.5S2 from internal mixture formation to external. Keywords: mixture formation, heat release, gas fuel, propane-butane mixture, kinetic phase, diffusion phase, combustion process