ВЫБОР ПАРАМЕТРОВ ДЕМПФЕРА КРУТИЛЬНЫХ КОЛЕБАНИЙ 4-ЦИЛИНДРОВОГО ДИЗЕЛЯ

Abstract

Torsional vibration dampers in modern internal combustion engines are used to reduce alternating shear stresses leading to fatigue failure of the crankshaft, as well as to diagnose the crankshaft, reduce oil consumption, increase the mechanical efficiency of the engine, and reduce noise. Torsional vibration dampers are suggested to be used at OJSC “MINSK MOTOR PLANT” Holding Managing Company” to improve the technical level of four-cylinder diesel engines. Damper parameters choice is based on torsional system model research, which is equivalent to the torsional diesel system of a 4ЧН (4ChN) 11×12.5 diesel engine. The amplitudes of the crankshaft nose torsional vibrations with the engine running are calculated according to the full-load curve. It was found that the maximum amplitude of vibrations corresponds to the diesel engine operation at a rated speed of 1000 rpm. In this case the amplitude of twisting of the crankshaft nose is 0.123 deg. For this diesel engine operating mode, the moment of inertia of the liquid damper flywheel and the damping coefficient were determined. They ensure a decrease in the torsional vibrations amplitude by more than three times. The calculation determined the expected decrease in the torsional vibrations amplitude for other modes of engine operation according to the full-load curve. In the entire research of crankshaft rated speed, the amplitude of nose torsional vibrations when using a damper is three times lower than without it. For experimental refinement of the damper parameters, a damper design with a variable moment of the flywheel inertia, as well as the possibility of replacing the polymethylsiloxane fluid are proposed.