The influence of the SCM structure parameters on the engine vibration and optimization the engine power

Abstract

In this paper, based on the slider-crank-mechanism (SCM) dynamics model, the dynamic parameters of the engine including the eccentricity () between crankshaft centre and cylinder centre of the SCM, the length and radius of the connecting rod and crankshaft, and engine speed are researched on the engine vibration and power, respectively. The dynamic parameters are then optimized based on the multi-objective genetic algorithm developed in MATLAB software to improve the vibration and power of the engine. Both the values of the maximum friction force and maximum torque are chosen as the objective functions. The research results show that the length of the connecting rod (), radius of the crankshaft (), eccentricity , and engine speed () significantly affect the vibration and power of the engine. With the optimized dynamic parameters of 136 mm, 45 mm, 14 mm, and 1850 rpm, the amplitude of oscillation of piston acceleration and the maximum friction force are reduced by 36.3 % and 12.5 % while the maximum torque is increased by 18.6 % in comparison without optimization. Therefore, the vibration and power of the engine are improved.

Controlling isolation system of initial combustion engines

“…To determine the vibration excitation source of the engine, the gas pressure 𝑃 in a cylinder measured based on the experiment result at 2000 rpm of an engine in Ref. [10][11], as shown in Fig. 3(a), is used to calculate the impacting forces of 𝐹 and 𝐹 .…”

“…The vibration studies on internal combustion engines showed that, in the low frequency regions of the engine below 100 Hz, the acceleration response of the engine was relatively high [9][10][11], and it also significantly affected the ride comfort of vehicles when the engine's vibration excitation was combined with the vibration excitation from the rough road surface. Besides, the existed studies had also shown that the engine isolation system mainly used by the traditional rubber mount (TRM) had not yet been effective enough in isolating vibrations of the engine.…”