Study on Diesel Engine of Locomotive Running on Qinghai-Tibet Railroad

摘要

Qinghai-Tibet railroad is located on the earth ridge and there a section of 965 km's long which altitude is above 4000m. The highest altitude in this section is 5072 m which is at the Tanggulashan Mountain Pass. The annual mean barometric pressure is 544 mbar. The maximum and minimum annual atmospheric temperatures in Qinghai-Tibet railroad are 35℃ and -45℃ respectively. So thin air, heavy wind & sand, large temperature difference in seasons and in a day form the greatest difficulty for diesel engine application and they are the important factors to cause worsening of engine combustion process, unstable matching features of engine & turbocharger and restraint of engine's effective power output. In this case, the conventional designed locomotive engine can not be adapted to the hauling need of locomotive in Qinghai-Tibet railroad. In order to make the engine suitable for the plateau conditions to the utmost, study on characteristics of engine supercharging system, turbocharger, intercooler and components in cooling system, fuel injection rules in various ambient conditions, influence of atmospheric temperature and pressure on pyrology performance have been carried out. On the basis of study, engine analog rig test of it s pyrology performance features and turbocharger matching & optimizing tests at high altitude railroad condition have been carried out. The test result that has consistency with calculation & analysis result has been obtained.