Application of steam injection in De-activated cylinder for exhaust waste heat recovery

Abstract

The exhaust gas and CO2 regulation in the automobile industry are becoming stricter due to the global warming and air pollution concerns. Researchers have thus been attempting to improve the thermal efficiency of engines beyond the limits of in-cylinder techniques. One possible technic that could be used to satisfy emission regulations is to install a waste heat recovery in future vehicles. Unlike other relatively advanced researches, this work used the engine itself as an expander for the proposed waste heat recovery system. Before coducing an engine experiment, a 1-D engine simulation was performed to verify how much energy could be regenerated from the exhaust gas. A majority of this increment was the result of steam injection work. The brake thermal efficiency was improved from 31.5% to 38.0% under the condition of BMEP 5 bar in a 1.6 L spark-ignition engine. These results were, however, based on the ideal assumptions. © 2017 The Korean Society of Mechanical Engineers.