The influence of constructive parameters of the engine on the size of pulsations of the stream of crankcase fumes

One of shortcomings of the method of definition of the condition of cylinder piston group on the con-sumption of crankcase gases is its high error. It is connected first of all that at measurement of a con-sumption of crankcase gases it is necessary to meet such negative effect as their pulsation. The size of pulsations of crankcase gases in different designs of engines differs greatly, and the error of the considered method widely varies. For the es-tablishment of the reasons causing the pulsation of the stream of crankcase gas at the measurement of its expense the technique of theoretical and bench researches is offered. The calculation of size of change of volume of the case of internal combus-tion engines for the angle of rotation of a cranked shaft was carried out for the main most popular designs by quantity and the arrangement of cylin-ders. For the comparison of the values of pulsa-tions of different designs the design parameters of the cylinder-piston group and crank gear were at-tached to the engine ZMZ-406. It was proved by the conducted researches that the main reason of dif-ference of size of pulsations of crankcase gases at different internal combustion engines, depended on such design data of the engine as the number and the arrangement of cylinders, the corner of the blocking of a cranked shaft. The engines which were most suitable for this method were revealed. These were line 3-, 5-and 6-cylinder, and also V-shaped 6-, 8-and 12-cylinder engines. The ap-plication of this method but nevertheless with a big-ger inaccuracy (approximately for 3-10 % depend-ing on the sensitivity of a flowmeter), for line 4-cylinder, 2-cylinder with the corner of a blocking 180 ˚ and V-shaped 4-cylinder engines is also possible.