Simulation study on exhaust turbine power generation for waste heat recovery from exhaust of a diesel engine

Abstract

Diesel engine has been used as the primary mover in vehicles for a long time. It is known that around 25%–30% of the fuel energy is wasted in the exhaust gas from diesel engines. In this study, a turbine power generation system including a 1.8 kW 60,000 r/min high-speed permanent magnet generator and a micro exhaust gas turbine, which is coupled to a diesel engine is designed and modeled to investigate its potential for recovering the wasted energy in the exhaust gas from a diesel engine. Computational models are set up using GT-POWER, MATLAB/SIMULINK and ANSOFT software. The performance and characteristics of the generator, the exhaust gas turbine and the engine are investigated. The simulation results showed that the exhaust turbine power generation system recovered the energy from the engine exhaust gas to generate electrical power. Simultaneously, the maximum power generated is 1.8 kW when the turbine speed is 60,000 rpm. The system efficiency reached its peak of 42.8% when the engine speed is 3000 rpm Last but not least, the electromagnetic characteristics of high-speed permanent magnet generator, which is coupled to an exhaust turbine, are also discussed and presented.

Keywords

• Exhaust turbine
• Energy recovery
• High-speed permanent magnet generator
• Generator electromagnetic characteristics
• System efficiency