Key Retrofitting Technology And The Application Research On Electronic Controlled Diesel/LPG Dual-fuel Engine

With the increasing of existed vehicles which cause such serious problems as energy shortage and pollution, and the rising of crude oil price, liquefied petroleum gas (LPG) as alternative fuel for vehicles was paid more and more attention. Diesel engines are widely used in various areas of national economy, and have been playing an extremely important role in human life. However the main application of liquefied petroleum gas on diesel engine was mechanical controled, hence, it would be important economic and social value to research the realization of LPG electronic control based on diesel engine.On the base of analyzing existing technology LPG using on petroleum-fueled cars and aiming at structural features of diesel engine as well as reform principles of dual-fuel engine, the paper puts forward the technical scheme of diesel/LPG dual-fuel engine with the main characteristics as electronic controlled sequential multiple injection. Besides, the paper studies the key technologies therein, mainly including blending strategy of dual-fuel engine, logic control process of the system, data algorithm and management of the control system.Performance comparison experiment of reformed dual-fuel engine and pure diesel engine is done on engine test-bed. The result shows that compared to pure diesel engine, dynamic performance of the dual-fuel engine basically unchanged, particulate emission reduces by a large margin. In middle and high load, diesel replacement rate reaches43.04%, mixed proportion average out to43.33%,mean fuel cost reduces11.23%either. In addition, road test of dual-fuel vehicle is done either, the result is basically consistent with that of test-bed.The paper tentatively puts forward a deduction method that independent of diesel engine bed-test, just demarcating the oil pump, LPG common rail, reasonably selecting the objective replacement rate, and programming the deduced LPG blending strategy computational procedure of diesel engine with matlab GUI interface, and doing experiment to testing the deduced LPG blending strategy. Facts proved that the deduction method has some practical value.