Analysis Of Overall Layout And Power System Matching For LNG Vehicles

Energy shortage and environment pollution have been a severe problems in recent years.as an alternative sources of energy,LNG automobiles has been developed rapi-dly with the development of natural gases industry.The LNG trucks will be the prim-ary developing directions of gas trucks due to its clean and economical characteristics.This study is funded by "LNG heavy load truck",which is a key scientific and tec-hnological special project of Shanxi Province.In this paper,took a LNG tractor as th-e target model,the simulation model of LNG truck has established and the power pe-rfrormance anrl econnnmy performance have been analyzed in CDUISE software.The optimal matching scheme is obtained by orthogonal test for factors of gearbox and fi-nal drive speed ratio.Firstly,the LNG car layout principle,the main component layout requirement and LNG gas cylinder was demonstrated,stress analysis was made for LNG cylinder pos-tposition using Hypermesh software.The evaluation index for power performance and economy was introduced briefly.The principle power performance comprise of such i-ndexes as maximum speed,maximum gradability,acceleration time of dir-ect drive to accelerate from 30 to 80 km/h and acceleration time from zero to 80 km/h.The econ-omical evaluation index include isokinetic hundred kilometers fuel consumpt-ion and h u-ndred kilometers fuel consumption of six conditions for heavy load cars.The external characteristics and mapping characteristics data is handled by MTAL-AB software for two kinds of LNG engine,which are WP12NG380E40 and WP10N-G300E40.The mathematic model of primary component including clutches,gearboxes,fi-nal drive,brakes and tire are established,then the simulation model of LNG load car is developed by CRUISE software.Both the power performance of unload and full load and the economy property of LNG trucks is calculated and analyzed,the power performance include maximum gradability,maximum acceleration,maximum speed,ac-celeration time of direct drive to accelerate from 30 to 80 km/h and acceleration time fom zero to 80 km/h,Whereas the economy property refers to isokinetic hundred kii-ometers fuel consumption from 30 to 80 km/h and hundred kilometers fuel consumpti-on of six conditions,special attention is paid for overload trucks.Eventually,the ove-rall properties of LNG trucks is obtained.Different gearbox and final drives are chosen to combine as several scheme acco-rding to the available product on the market,orthogonal test is carried out and the o-ptimal scheme is chosen from the orthogonal experimental results based on range ana-lysis theory.The optimal scheme is transmitted into CRUISE software and the numeri-cal model is established and the overall performance of the truck is calculated.The r-esults shows that,compared to original scheme,despite the climbing and acceleration performance are decreased slightly,the maximum speed of the truck is increased by 10.08%,the fuel consumption is improved by 17.72%and the economy performance is improved significantly.