Experimental Study on Operating Characteristics of On-Board PEMe Hydrogen Generator Integrated with a SI Engine

Abstract

In this paper, operating characteristics of an on-board proton exchange membrane electrolysis (PEMe) hydrogen generator integrated with a spark ignition (SI) engine were investigated. The effect of H2 and O2 produced by the PEMe, which is fed by the engine charging system on the in-cylinder combustion and engine performance parameters, was investigated experimentally for different engine operating conditions. Also, the PEMe inlet water was heated by a copper pipe passing through a heat exchanger positioned on the engine exhaust path to decrease the PEMe power requirement. Therefore, improving the engine performance parameters by decreasing the engine charger system activity was attempted. The SI engine was operated along with integrated on-board PEMe for different engine speeds, throttle positions (TP), and engine loads. As a result, an on-board PEMe hydrogen generator system integrated with a SI engine caused improvement of the performance parameters (i.e., brake power, brake torque, brake thermal efficiency, and brake specific fuel consumption) in the range of 3.16–4.4% when the engine was operated with 1/2 TP and a range of 1,6–3,6 rpm. However, the low and medium speeds of the engine are more advantageous than high engine speeds with regard to the on-board PEMe system efficiency.