The Design Of Reformer And Its Driving System Of On-Board Fuel Reformation For An Homogeneous Charge Compression Ignition Engine

In recent decades, with the development of the national economy, the inventory ofautomobile in our country increases dramatically. This brings us a great influence on economyand environment, and it has been a big challenge to decrease the automotive fuel consumptionand emissions. For the sake of lessening the dependence on oil resources and reducing theenvironmental pollution, the development of the new combustion technology becomes anextreme important issue.HCCI, Homogeneous Charge Compression Ignition, is a new combustion mode of theengine. This is one kind of combustion that happens after compressing the mixture of fuel andair to an auto-ignition temperature. A wide range of fuels can be used by HCCI engines. AndHCCI has very low emissions of NOxand PM. Thus it becomes a popular research field of thedevelopment of the internal combustion engine.Fuel on-board reformation is a very positive research to realize the control of HCCI andextend the operation range. The electro hydraulic driving system of the reformer has acompact structure. It can realize variable valve timing and extraordinarily improve thecontrollability of the valve of the reformer. Thus the reformer may inject the reformed gas andthen capture the high temperature burned gas in appropriate time according to the engineoperation condition.In this thesis, the structure of reformer and its driving system are designed according to thestructure and characteristics of the test HCCI engine. The paper introduces the currentresearches and the features of different valve systems after reviewing a lot of literatures. Italso explains the concept and performances of HCCI, and analyzes the methods of extendingthe limit of the HCCI combustion and fuel reformation. According to the demand of HCCIsystem, an overall design of the reformer is proposed, and the calculation and design of thehydraulic element of the driving system is carried out. Considering the structure of thissystem, the thesis describes the requirement of electronic control system, the relative sensorsand actuator, and accomplishes the hardware designing and software programming. And itdesigns the relative circuit, ECU and other electron components. Finally, the simulated resultsindicate that the system may achieve the expected functions.