INTERNAL COMBUSTION GAS ENGINES IN SYSTEMS FOR INCREASING THE EFFICIENCY OF FUEL ELEMENTS OF LARGE ENERGY FACILITIES

Abstract

The proposed article analyzes the potential possibility of increasing the efficiency of an energy complex with a gas turbine and solid oxide high-temperature fuel cells, into the structure of which an auxiliary piston gas engine of internal combustion is integrated. Natural gas, methane was used as an energy carrier. The subject of the research is indicators of the working process of the auxiliary engine when it is working on mixed gas fuel (carbon monoxide - methane) of variable composition. The research was carried out by the computational and analytical method using a simplified method of calculating the working cycle of a piston engine. Solutions to several problems are considered: disposal of carbon monoxide emissions at the exit from fuel cells during their heating; provision of an additional source of electrical energy for powering methane conversion devices and an additional source of heat for its steam-plasma conversion; utilization of carbon monoxide and residues of incomplete methane conversion. Calculation studies of indicators of the working process of an auxiliary gas engine with a capacity of 100 kW on mixed fuel of variable composition (carbon monoxide - methane) show its stable operation with appropriate correction of the fuel supply regulation system. The effective efficiency coefficient in the entire range of fuel concentration slightly changed (from 0.369 to 0.380). Its growth is observed with an increase in the proportion of methane in the mixed fuel. The average effective pressure of the cycle practically does not change, and the maximum pressure of the cycle during engine operation in the entire range of changes in the composition of the mixture is at the level of 8.0 MPa. Slight change in the maximum temperature with an increase in the concentration of methane in the fuel mixture (from 2117 K to 2048 K) has been noticed. The research testified to the effectiveness of the proposed method of improving the environmental and economic characteristics of the energy complex with fuel cells, by including in its structure an auxiliary gas engine with minimal cost adaptation for operation on mixed fuel of variable composition.