1976 年 37 巻 4 号 p. 481-488
This paper deals with the theoretical relations between the blowback into the crankcase and the performance of industrial and farm use small two-stroke cycle engines of Schüurle type with some types of cylinder ports.
In order to carry out systematic investigations of the above mentioned, we made cycle simulations of the delivery and the scavenging processes.
The simulations were conducted in the following cases.
1. (a); Inlet pipe, exhaust pipe and scavenging passage were neglected,
(b); inlet pipe, exhaust pipe and scavenging passage (as pipe) were considered, and
(c); inlet pipe, exhaust pipe and scavenging passage (as volume) were considered.
2 Three conditions of perfect stratification, perfect diffusion and half diffusion were considered.
3. (a); Variable values of adiabatic indices were used,
(b); the vaporization of gasoline was considered or not, and
(c); the heat conduction from the wall of cylinder and piston to the mixture gas considered or not.
The conclusions obtained by the investigations (1, 2, 3) above mentioned are as follows.
(1) In the first, (c) is the nearest to the condition of the actual engines.
(2) In the second case, the condition between perfect diffusion and half diffusion is near to that of the actual engines.
(3) In the third case, the influence to the engine performance of the modification is the most at (c).