The use of liquefied petroleum gas as fuel in tractor diesel engines

BACKGROUND: The use of liquefied petroleum gas (LPG) as alternative helps to eliminate a number of drawbacks related to fuel-air ratio. The high-priority problem is development of means and methods of reduction of environment pollution, specifically targeted researches in the field of alternative fuel with minimal harmful emissions into the environment, increase of availability of this technology by means of reducing the costs of adaptation of the fuel injection system of a diesel engine.

AIMS: The main aim of the study is justification of parameters of the diesel engine operating according to gas-diesel cycle with the spark dose ignition.

METHODS: The studies were carried out at the brake bench equipment of the MMZ D-243 diesel engine. The distributed liquefied petroleum gas (LPG) supply system with an ignition dose of diesel fuel was tested with automatic change of the gas supply angle and including exhaust gases in the intake manifold in the recycling system. Adaptation of the diesel engine to LPG allows the fuel injection system to operate in both diesel and gas-diesel mode, while the electronic regulation of the diesel fuel supply in the "diesel" mode occurs more accurately and helps to reduce the consumption and final combustion of diesel fuel in the exhaust manifold. The standard equipment for distributed LPG supply widely used for transferring gasoline engines with spark ignition is applied. The chosen domestically made electronic control unit was configured according to the methodology for controlling the gas supply in the cylinders developed in Federal Scientific Agroengineering Center VIM.

RESULTS: The studies showed that the emission of pollutants into the atmosphere decreased in all operation modes of the engine in the gas-diesel mode and complies with the Euro-5 standard. Due to the 2,5 times lower price of LPG compared to diesel fuel, the cost of using LPG as a replacement for diesel fuel in the "gas diesel" mode is reduced by 25–30% of the cost of agricultural crops. The use of LPG in gas-diesel engines reduces the cost of agricultural products by 15–18%.

CONCLUSIONS: These indicators confirm the relevance of scientific research in the development of the diesel engine adaptation system. The gas-diesel fuel injection system of the engine is the main effective way to reduce diesel fuel costs.