Optimization and Evaluation of a Low Temperature Waste Heat Recovery System for a Heavy Duty Engine over a Transient Cycle
Powertrain efficiency is a critical factor in lowering fuel consumption and reducing the emission of greenhouse gases for an internal combustion engine. One method to increase the powertrain efficiency is to recover some of the wasted heat from the engine using a waste heat recovery system e.g. an organic Rankine cycle. Most waste heat recovery systems in use today for combustion engines use the waste heat from the exhaust gases due to the high temperatures and hence, high energy quality. However, the coolant represents a major source of waste heat in the engine that is mostly overlooked due to its lower temperature. This paper studies the potential of using elevated coolant temperatures in internal combustion engines to improve the viability of low temperature waste heat recovery.