Turbocharged Loop Scavenge Diesel Engine

Abstract

This paper describes the application of turbocharging to the loop scavenge diesel engine. The first part is concerned with the important effects on the practicability of the cycle of the turbocharger efficiency, scavenge air pressure and temperature, exhaust pressure and temperature, and the pulses in the exhaust, the allowable maximum pressure in the cylinders, the pressure drop across them in relation to the air flow and the air utilization of the engine. It then goes on to a discussion of the way in which these many factors may be arranged to result in a practical engine of high efficiency and utmost reliability. Reasons are given for preferring, in the present state of knowledge, to retain the crankshaft-driven scavenge pump and the merits of series and parallel arrangements are discussed together with the possibilities of cooling during the compression stages. The application of these considerations to the development of a range of engines is described. Results of tests on the berth and in service are given together with some details of the mechanical design and construction.