A four-cylinder, four-stroke diesel engine is used to generate an output of 200A at 210V. The generator
Question:
A four-cylinder, four-stroke diesel engine is used to generate an output of 200A at 210V. The generator and mechanical efficiencies are 90 % and 87%, respectively. The quantity of fuel supplied to the engine is 10 kg/h with a mass analysis of 86.2 % carbon and 13.8 % hydrogen. The molecular weight of the fuel is 167 g/mol. Assume that the products of combustion are CO2, H20 and N2 with 20 % excess air. The specific gravity of the fuel used is 0.84 and the formula for the higher heating value from the Bureau of Standard is: HHV = 22,230 - 3,780(S.G.^2) BTU/lb. The jacket cooling water for the diesel electric power plant flows at 0.25 kg/s which is first used to lower the temperature of the lubrication oil through an indirect oil cooler. The jacket cooling water enters the oil cooler at 29 C and leaves at 32 C in which it will be then used to cool the diesel engine. The jacket cooling water leaves the engine at 60 C. The exhaust gas temperature is 300 C and about 1.2 kg of steam is formed per kg of fuel. The exhaust gas is composed of steam and dry gas with specific heats of 2.1 kJ/kg-K and 1.02 kJ/kg-K, respectively. The ambient temperature is 28 C.
1. Draw the schematic diagram of the diesel-electric power plant
2. Solve for electric power, brake power, indicated power, heat supplied, loss in jacket water, loss in oil cooler, loss in exhaust
3. Tabulate an energy balance sheet
Thermodynamics An Engineering Approach
ISBN: 978-0073398174
8th edition
Authors: Yunus A. Cengel, Michael A. Boles