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.

The article discusses the possibility of using blended biofuels from rapeseed oil (RO) as fuel for a diesel engine. RO blended diesel fuel (DF) and emulsified multicomponent biofuels have been investigated. Fuel physicochemical properties have been analyzed. Experimental tests of a diesel engine D-245 in the operating conditions of the external characteristic curve and the 13-mode test cycle have been conducted to investigate the effect of these fuels on engine performances. CFD simulations of the nozzle inner flow were performed for DF and ethanol-emulsified RO. The possibility of a significant improvement in brake thermal efficiency of the engine has been noted. The efficiency of using blended biofuels from RO as a motor fuel for diesel engines has been evaluated based on the experimental test results. It was shown that in comparison with the presence of RO in emulsified multicomponent biofuel, the presence of water has a more significant effect on NOx emission reduction. The content of RO and the content of water in the investigated emulsified fuels have a comparable influence on exhaust smoke reduction. Nozzle inner flow simulations show that the emulsification of RO changes its flow behaviors and cavitation regime.

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The fundamentals of kinematics and dynamics of transport piston internal combustion engines made using different layout schemes are presented. Along with the traditional in-line, V-shaped, including oppositional, arrangement of cylinders, schemes with "staggered" arrangement of cylinders in the block at the displaced connecting rod necks of the crankshaft of the engine are considered. The kinematics of the coaxial crank mechanism is considered in detail. The questions of dynamics with reduction of calculated dependences of forces, moments, a choice of a rational order of work of cylinders in relation to the considered kinematic schemes are in detail stated. Considerable attention is paid to the unevenness of the crankshaft rotation speed and engine balancing. The loads on the main and connecting rod bearings of the crankshaft, the knowledge of which is necessary in determining the bearing capacity of bearing units, are also considered. Meets the requirements of the Federal state educational standards of higher education of the last generation. For students of higher educational institutions studying in the direction of training 23.03.03 "Operation of transport and technological machines and complexes" and related areas.