A study or the breathing performance of four-stroke
internal combustion engines with particular emphasis on
heat transfer during induction is presented. An experimental
study into inlet port heat transfer has been conducted, and
the following law has been established for a compression
ignition engine assuming a quasi-steady heat transfer
process : Nu = 3.155 Re 0.53. A similar study of the heat pick-up of a spark ignition
engine inlet port has failed to produce such a
relation. The Nusselt number has been found to increase
with Reynolds number initially and then decrease,
Figs. (47, 48, 49). This was the case even when this
engine was operated with gaseous fuel suggesting that
fuel evaporation was not the cause. Theoretical calculations indicats the inlet port
heat transrer is very important and reduces the volumetric
efficiency by about 5.5% on average. The combined reduction
in volumetric efficiency due to inlet port and cylinder
heat transfer amounts to l4% on average, depending on the
engine speed. An extensive literature survey of the various
aspects of induction is also presented.
The differential equations involved were solved
numerically using an electronic digital computer.
A Master's Dissertation, submitted in partial fulfilment of the requirements of the award of the Master Of Science degree of Loughborough University.