SIX STORKE ENGINES: OPERATING PROCEDURE AND SCHEMES OF CRANKSHAFTS
The article is devoted to the perspective direction of development of internal combustion piston engines - realization of six-stroke working processes. The article presents an overview of possible options for the implementation of six-stroke cycles, known types of engines. The greatest interest is the six-stroke cycle with two working strokes of the piston, one of which is carried out under the pressure of the combustion products of fuel, and the second - under the pressure of steam formed as a result of water supply to the cylinder. This cycle is implemented in the Crower engine It is shown that the six-stroke cycle has a number of advantages over the four-stroke cycle: its implementation improves the economic and environmental performance of the engine, reduces the temperature level of parts, which has a positive effect on resource performance. On the basis of published indicator diagrams of six-stroke engines, diagrams of the total torques of four-cylinder engines operating on four-stroke and six-stroke cycles are constructed. It was found that the implementation of a six-stroke working cycle with additional injection of water into the cylinder leads to some deterioration of the uniformity of the alternation of the working strokes and the uniformity of the torque. The use of special schemes of crankshafts can contribute to some improvement in these indicators. Recommendations on the use of crankshafts with cross-shaped schemes in six-stroke engines are given The presented research technique can be used to select the preferred design of crankshafts for engines with different number of cylinders. Given the need for the preparation and storage of distilled water in the implementation of the six-stroke cycle, the conclusion is made about the possibility of using six-stroke engines as part of marine power plants. The necessity of further research of kinematics, dynamics and vibration activity of six-stroke engines is pointed out.