Hydrogen enrichment of an internal combustion engine via closed loop thermochemical recuperation

Hydrogen enrichment in an internal combustion engine can greatly improve efficiency and at the same time reduce emissions without the need for extensive engine modifications. One option for a hydrogen source for the enrichment is actively producing hydrogen on-board the vehicle through steam reformation of methane. This process requires thermal energy to run however. In theory this thermal energy could come from the excess heat available in the exhaust gas of the engine. Though this has been explored theoretically no experimental results exist. This report describes a design for an experimental set-up to give a proof of concept for such a closed loop thermochemical recuperation system. The main components are a methane fueled ICE with electric generator and a catalytic reformer. A number of water and gas heaters are also added to pre-heat the water and gas before entering the reformer. Measurement and data acquisition equipment are specified as well as an algorithm for the controllers. The limited budget available for the project means that some engine operating parameters, such as the air to fuel ratio and engine speed are not electronically actuated and therefore have to be controlled manually. Even though the system will operate mostly in steady state conditions, especially the air to fuel ratio control might prove to be difficult as a result of the changes in the fuel composition during start-up. The goal of this project however is to get some first practical experience with the proposed system and for this the proposed set-up will suffice