FIELD: testing.
SUBSTANCE: invention relates to the studies of the physico-chemical properties of fuels of various component, hydrocarbon, and fractional composition, and can be used to determine the ignition delay time of liquid and gaseous fuels with respect to piston internal combustion engines. Proposed is a method for evaluating the regulation compliance of motor fuels for internal combustion engines according to an expanded indicator diagram consisting of the ignition delay, fast burning, slow burning and afterburning phases, wherefor, the current values of pressure of the cylinder gases in the combustion chamber of the engine with a discreteness of 40 ms and the angle of rotation of the crankshaft are recorded, an expanded indicator diagram in the coordinates "cylinder gas pressure — angle of rotation of the crankshaft" is built, and with the pressure remaining constant for a certain period of time with a ±4% deviation, said period of time is taken as the ignition delay period. Additionally, the engine is operated under identical conditions without injecting fuel into the combustion chamber, with an expanded indicator diagram built, aligned with the expanded indicator diagram of the engine with the fuel injected, the point of divergence of the cylinder gas pressure diagrams after the end of the ignition delay period and the point of aligning of the diagrams, taken as the end time of heat generation, are recorded, followed by measuring the area defined by the indicator diagrams between the points of divergence and aligning of the indicator diagrams with and without fuel injection and comparing said area with the area of the indicator diagram taken on a reference fuel sample under identical operating conditions of the engine, and with the difference between said areas equal to ΔSi≤0.0045 c.u., the fuel is considered regulation-compliant.
EFFECT: lower labour intensity of evaluating the efficiency of combustion of motor fuels in an internal combustion engine.
1 cl, 2 dwg, 1 tbl
