Research on the Characteristics of Turbocharged Diesel Engines : 2nd Report, The performance of variable speed engines

Abstract

A method of calculating the equilibium operating performance of turbocharged Diesel engines has already been developed by the present authors under the following assumptions ; 1. blow down energy of the exhaust gas is completely converted into heat, which is added to the gas, 2. turbine is a pure steady flow type, 3. the Diesel engine is operating on the Sabathe cycle with a given compression ratio and a constant pressure ratio, 4. charging temperature is equal to the outlet temperature of compressor. In the previous report, the calculation is confined only to the constant speed engine. However, in this paper, the same method is extended to the variable speed engine in which load varies in proportion to cube and square of engine speed respectively. Further the performance of the engine working on the maximum torque at every speed is calculated, assuming that the maximum torque will be obtained at the definite excess air ratio.