柴油机是把燃料的化学能转变成热能,再把热能转变成机械能的一种装置。要使柴油机获得较高的功率,就必须使燃料烧得完全、及时,并要把得到的热能尽可能多地转变成机械能。为了达到这一目的,十九世纪末出现了增压柴油机,本世纪初又出现了废气涡轮增压,利用排气能量来提高进气压 Diesel is a device that converts the chemical energy of a fuel into heat and then heat into mechanical energy. For diesel engines to obtain higher power, it is necessary to burn the fuel completely and in time, and to convert as much heat as possible into mechanical energy. To this end, turbocharged diesel engines appeared at the end of the nineteenth century and exhaust turbines were also introduced in the early part of the century, using exhaust energy to increase intake pressure