Balancing of the moments of the VR-5 type engine taking into account the desaxial and the cylinder camber angle

Abstract

Recently, V-engines with a small angle of camber are more widely used as power units for passenger cars, especially because of the reduced engine length, and the transverse dimensions are almost the same as in-line ones. All this leads to an increase in overall engine power. However, due to the small camber angle between the parallel rows of cylinders, the intersection of the cylinders in their lower part may occur. To prevent the latter, significant multidirectional desaxial is used. Moreover, the calculation of the dynamics of similar engines introduces a number of features, including balancing the inertia forces and their moments from the reciprocating moving and rotating masses. The article discusses the balancing of 5-cylinder four-stroke VR type engines with desaxial crank mechanism and uniform flash alternation. The formulas allowing to find and analyze moments of the inertia forces of the reciprocating and rotating masses arising in VR-5 engines are given by the given value of the cylinder camber angle, the ratio of the crank radius to the connecting rod length and the relative displacement of the cylinder axis. A method of balancing the moments of inertia forces of the reciprocating and rotating masses is proposed and the results of the presented dynamic study of a VR-5 engine using analytical, software and graph-analytical methods.

Calculation Procedure for Sliding Bearings of a Reciprocating Engine

“…A decrease in the thickness of the lubricant layer below the critical value [5,6] leads to an increase in friction, along with heating and wear of the bearing. Motor vibration due to engine roughness also influences bearing wear [5,7,8].…”

“…Fitting the characteristic curves χ(Φ) [3,7] by exponential equations was carried out using the pwrfit functions [11] built into the Mathcad program. Approximating functions for the relative eccentricity χ as a function of load factor Φ at various ratios of the bearing length L to the bearing diameter d are shown in Table 1.…”