Study On Experiment Of Cold-start In Hydrogen-Gasoline Ignition Engine

With the continuous development of economy, China’s automobile production isincreasing. By2014, China has been the biggest automotive production country in the worldfor six years. The increase of automibile makes a problem of fuel consumption andenvironmental pollution. During the cold-start condition, the status of engine is unstable, thepollution emissions is serious. Since2010, in the fourth stage of the pollution standard,China has incresed in the limits of cold-start pollution emissions. As a new clear energy, thecombustion characteristic of hydrogen is excellent, the combustion products is non-pullution.The research of hydrogen improve the cold-start performance of gasoline engine issignificance.Based on the NSFC project of “Study on Energy-saving Mechanism of HEV Equippedwith Lean-burn Gasoline Engine with Hydrogen Direct Injection System”, the enginecold-start performance of gasoline port-injection, hydrogen direct-injection and thecombination of both was studied in this thesis.We modified a4-cylinder4-stroke engine,equipped with a set of inlet injection system, designed the drive circuit. The engine is able torealize the hydrogen-gasoline dual fule burning. With the actual demand, designed thecontrol strategy of engine cold-start. Under different ignition timing, studied on theexperiment of cold-start with gasoline port-injection, hydrogen direct-injection and thecombination of both. The main experimental results are listed as follows:1)Under the cold-start condition of hydrogen direct-injection and the combination ofhydrogen and gasoline, the starting time of engine is short, the first cycle is ignitedsuccessfully. Under the cold-start condition of gasoline port-injection, the starting time ofengine is long, the first cycle can’t be ignited. 2) Under the cold-start condition of gasoline port-injection, the best ignition time is25°BTDC, if ignition time is too late, the engine is hardly start. Under the cold-start condition ofhydrogen direct-injection, the best ignition time is15°BTDC, if ignition time is too early,the engine is hardly start. Under the cold-start condition of the combination of hydrogen andgasoline, the best ignition time is15°BTDC, if ignition time is10°BTDC-30°BTDC,the engine is successfully start.3)Under the cold-start condition of the combination of hydrogen and gasoline, hydrogen islittle, but has a major role in the combustion, improves the speed of the mixture combustionand circulation constant volume.4) Under the cold-start condition of gasoline port-injection, the emission of HC and CO ishigher than the cold-start condition of the combination of hydrogen and gasoline. Under thecold-start condition of hydrogen direct-injection, the pollution emissions is less.