On the Effects of Length of an Intake Pipe on the Delivery Ratio in a Small Two-Stroke Cycle Engine

抄録

To examine the effects of length of an intake pipe on the delivery ratio (or the breathing capacity) in a small crankcase-scavenged type two-stroke cycle engine, the authors have measured the amount of air flow and analyzed some pressure indicator diagrams for the intake pipe, the crankcase and the cylinder. Some conclusions obtained are summarized as follows : a) The maximum delivery ratio occurs on account of the inertia-effect same as in the case of four-stroke engine and the matching conditions for the inertia-effect are expressed by Z_M=ωL^*/a_s≅θ_s/270. b) In the special cases of a long intake pipe or high speed, the pulsation waves in the intake pipe have an influence on the delivery ratio and such pulsation effect is governed by q=15a_s/(N·L_s). c) Comparing these equations, it may be noted that the inertia-effect differs essentially from the pulsation-effect.