Research On Application Technology Of Natural Gas Vehicle

Since the industrial revolution, the demand of the fossil energy for originally andprimarily coal in many countries worldwide has been growing rapidly. The demand for oilsoared in the1960s, and it has been dominating energy in the world. With the emergence ofthe oil crisis and the demand increasing gradually for natural gas, NG has become one of thethree main fossil fuels. Since the21st century, governments around the world have intensifiedthe efforts on the development and application of new energy and renewable energy, theenergy structure with new energy has formed. Although the proven reserves of natural gasaround the world in nearly20years has increased, the consumption of total energy is alsoincreasing constantly with the development of the industry. The lack of world energy led inmore fierce competition for energy resources. The shortage of oil resources and the matureapplication technology of natural gas in the world made the nations of the world focus oneconomic and environmental benefits of natural gas and took the development and applicationof natural gas as an important direction. In China, natural gas is developing rapidly and thenumber of CNG vehicle and LNG vehicle is also increasing. In2013there are1.577millionnatural gas vehicles, CNG vehicles having large proportion and mainly taxis and buses. Thegovernment of Republic of Yemen in recent years also has intensified the development ofnatural gas, cooperated with abroad NG companies, established lots of NG processing plantsand stations, and began the development of domestic natural gas vehicle.Compared with the traditional gasoline engine and diesel engine, NG engine has moreadvantages and some disadvantages of poor power performance and the difficulty of startup.Many scholars from all over the world are actively devoting themselves to automobileapplication technology, including control system of natural gas supply, combustion andemission characteristics, natural gas liquefaction technology and light gas cylinders,diesel/natural gas dual fuel and gasoline/natural gas dual fuel engine technology and specialnew type natural gas engine lubricating oil and so on, and made a great breakthrough andresearch achievement. In this paper, NG application technology was studied from four aspects, includinglubricating oil of CNG/gasoline dual fuel engine, fault simulation test research, technicalconditions of in-use vehicle modification natural gas, and LNG/diesel dual fuel engine testresearch. The study found that for flexible-fuel automobile, engine operating condition isslightly different between the model of gas and fuel. CNG/gasoline flexible fuel enginespecial lubricating oil helps to reduce the wear of moving parts, improve the effect of thepurity of lubricating oil, and improve the lubrication performance of the engine. Flexible fuelautomobile engine fault simulation could help diagnose and solve the problems and failureswhich are caused by all kinds of sensor or gas supply system components. In addition, thestudy in this paper found that too high or too low outlet pressure of the pressure regulatorhave a great effect on engine performance and emissions, choosing appropriate outlet pressureof pressure regulator and accurate ignition advance angle can improve the engine performance,and reduce exhaust emissions. Thus it may improve the overall performance of natural gasvehicle. With the rapid increase of modified natural gas vehicle, specification for refittingwork of in-use natural gas vehicle is formulated immediately in order to ensure the qualityand operation safety, the work by local government on the use of natural gas vehicle refittingis extremely urgent. This paper studied the modification conditions of natural gas vehicletechnology, and put forward “technical conditions of in-use vehicle modification natural gas”that is suitable to be implemented in Shaanxi Province. In addition, this paper carried out theresearch on application technology of LNG/diesel dual fuel engine, and analyzed theperformances of power output, economy and emission of dual fuel engine at variousoperational states under the condition of keeping the original torque.