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A phenomenological model is presented for prediction of the combustion characteristics of a Quiescent Chamber Diesel engine. Predictions with the model have shown acceptable agreement with a range of experimental data. The major physical processes controlling combustion have been characterised, and the dominant role of air entrainment and turbulent mixing confirmed quantitatively.

The importance of turbulent energy dissipation rate on smoke and unburned hydrocarbon from Diesel engines has been identified quantitatively, the latter through a quenching which is predominant at idling and load operation of the engine. A parameter has been derived to assess the contribution to unburned hydrocarbon emissions various design and operational character-of an engine. Further experimental data required to support the general validity of parameter.

Convective and radiative heat transfer measurements in a direct injection Diesel engine have been made using surface thermocouples and a pyroelectric radiation detector. Measured instantaneous local and spatially averaged convective heat fluxes agree with correlations for turbulent convection to flat surfaces, when using measured local air motion data. Two temperature zones were considered in the computation of local heat flux. Radiative heat flux measurements corroborate the findings of others, but lower flux levels are attributed to the high swirl engine used here. A proposal for computation of radiative heat flux from soot concentration shows promise.

A method has been presented for the determination of the turbulence characteristics in engine cylinders using hot wire anemometry, and high speed random signal data processing techniques. Results obtained on two engines show agreement with the findings of other workers. Data for Micro and Macro-scales of Turbulence are presented for the first time, and evidence put forward to suggest very weak dependence of the Microtime Scale λt with either engine speed or combustion chamber geometry.