Design and Simulation of Two Stroke Engines

Chapter 5 - Computer Modeling of Engines
Plate 5.2 A cut-away view of a 300 hp V8 outboard motor
(courtesy of Outboard Marine Corporation).
characteristics. This subtlety of design will be discussed below during the presentation of
data acquired by simulation.
Should the design approach given in Fig. 5.8(b) be extended to a four-cylinder engine,
then the manifold exit toward the exhaust box reverts to a three-way branch, normally mutually
at 90°, as that exit is now located in the middle of the bank of cylinders, i.e., between
cylinders numbered 2 and 3 of a four-cylinder unit. This is shown in Fig. 5.8(c). This is
particularly true for an automotive diesel or spark-ignition engine, but less correct to be stated
categorically if it is for an outboard design, as in Plate 5.2, where the branch lengths Li, L2,
L3, etc., are now of some considerable length in a design optimized for power and also where
space limitations may prevent full optimization of its potential.
5.3 Heat transfer within the crankcase
The heat transfer characteristics in the crankcase of a crankcase compression two-stroke
engine is not a topic found in the technical literature. Therefore, I present a logical approach
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