THE STUDY OF INTERRELATIONSHIP OF IONIZATION CURRENT AND MAXIMUM INDICATED PRESSURE DURING THE COMBUSTION OF HYDROGEN RICH GASOLINE-AIR MIXTURE

Ion current occurring in the result of chemical reactions of hydrocarbon fuel combustion is called the chemi-ionization current. The analysis of the research works displayed that the chemi-ionization current value can characterize the intensity and velocity of chemical reactions of burning in the combustion chamber of a piston engine, and therefore, the efficiency of heat generation during the combustion in the internal combustion engine. The paper shows that the study of the interrelationship of ion current and indicated combustion pressure determining, to the greatest extent, the workflow efficiency is the critical task, especially for gasoline engines with hydrogen transfer. The goal of the paper is to analyze the dependence of indicated combustion pressure and ion current under various initial conditions of fuel-air mixture combustion. Based on the experimental studies carried out on the single-cylinder motor unit UIT-85, the authors obtained data on the ion current occurring on the ionization sensor electrode remote from the ignition spark plug in the result of the flame front passing through it. Using the Kistler’s piezoelectric pressure sensor combined with the ignition spark plug, the authors created the indicator diagrams. The paper presents the data on the processing of the ion current peaks and the indicated pressure and the diagrams of their dependence on the mixture composition under various initial conditions. As the result of the study, the authors presented the diagram of the interrelationship of maxima of indicated pressure and ion current when varying the mixture composition at various crankshaft speeds, mass fraction of hydrogen added to the fuel-air mixture, compression and two angles of ignition advance.