Study On The Performance Of Gasoline Engine And Vehicle With On-board Hydrogen Generator

With the increasingly serious environmental problems,clean energy has become the inevitable trend of the development of internal combustion engines.As an alternative fuel for internal combustion engines,hydrogen has many advantages and is considered to one of be alternative energy source of internal combustion engines.However,at present,because the domestic and foreign hydrogen station infrastructure construction is not perfect,the problems in the hydrogen storage and transportation security lead to not large-scale applications of hydrogen in the automotive market the application of hydrogen in the automotive industry by hydrogen filling difficult problem,a large number of hydrogen storage will bring the car safety risk.Hydrogen production from water electrolysis is a relatively simple and effective way,which can solve the problem of hydrogen source of hydrogen-blended engine.On-board hydrogen generator produces hydrogen and oxygen by the extra power of engine generator,which is bound to affect the dynamic performance of the vehicle.The effects of hydrogen generator for vehicle fuel consumption by the methods of test and simulation and oxygen enriched intake air for engine dynamic performance,economy and emissions were studied.In this paper,a four cylinder,1.5L natural aspirated engine produced by BAIC group is introduced.On the prototype engine,hydrogen and oxygen nozzles were installed;a hydrogen generator was designed and manufactured;a self-developed hybrid electronic control unit(HECU)was used to control the injection pulses of the hydrogen and gasoline,hydrogen generator on-off and oxygen enriched intake air.Based on the characteristics of hydrogen and oxygen generated by hydrogen generator at the same time,the effects of oxygen enriched intake on the dynamic performance,economy and emission of gasoline engine were studied.The test selects the common speed 1500 rpm,2000rpm and commonly used MAP 42 kPa,68kPa as the test condition.The experiments were carried out under different operating conditions of 1500 rpm and 42 kPa,1500rpm and 68 kPa,2000rpm and 42 kPa,2000rpm and 68 kPa.Experimental results showed that the engine dynamic performance with oxygen-enriched was obviously improved,at different speeds and loads.The overall economy of oxygen-enriched intake air engine was improved.The emissions of oxygen-enriched intake air engine were both advantages and disadvantages.Oxygen-enriched air could significantly improve combustion environment,reduce HC and CO emissions,but due to intake oxygen concentration increased,higher combustion speed,temperature and pressure in cylinder combustion lead to increased NOx.The Map diagram of the internal combustion engine is obtained through the test bench.It could be concluded from the engine Map,the fuel consumption of the engine with hydrogen generator was increased compared with the original engine at the typical working conditions.The optimum operating range of hydrogen generator was found to be engine speed greater 1300 rpm and MAP higher 48 kPa through the bench tests.Based on the test data,this paper investigated the effect of hydrogen generator on engines with start-stop system and hydrogen start strategy by AVL-cruise.It can be concluded from the vehicle simulation results that the fuel consumptions of the vehicle adopting start-stop system are reduced by 8.43% compared to original vehicle when the hydrogen generator is operated within the optimum range.Due to the different length of idle time and starting times with start-stop system,the gasoline consumption is obviously decreased during the UDC while it has no obvious improvement during the EUDC.