The Effect of Inert Gas in the Mixture with Natural Gas on the Parameters of the Combustion Engine

The article discusses the influence of inert gases (carbon dioxide and nitrogen) in a mixture with natural gas on power and economic parameters of the internal combustion engine LGW 702 designed for micro-cogeneration units. The experimental measurements were made under various engine operating modes and under various compositions of fuel mixtures. The aim of the experiment was to analyze and assess the full impact of the inert components in the gaseous fuel, especially on the particular integral parameters, as well as on the internal combustion engine parameters relating to the course of burning the mixture. Experimental results indicate a decrease in performance parameters and an increase in specific fuel consumption with an increase in the proportion of internal gases in the mixture. Increasing proportion of inert gases leads to decreasing maximum pressure in the cylinder (a decrease approximately by 50% with the mixture CO2NG50 or by 30% with the mixture N2NG50, compared to natural gas) and the position of maximum pressure value is shifted further into the area of expansion stroke.