DK28 diesel engine accessories Advantages and disadvantages of diesel power unit

advantage

The greatest advantage of diesel power plant is its high thermal efficiency, and its fuel consumption is significantly lower than that of steam power plant. Most modern marine diesel engines are low-speed engines, with a speed of about 100 revolutions per minute, which can directly drive propellers. Especially in the early 1980s, long stroke and ultra long stroke low-speed engines appeared. The speed per minute dropped to below 70 rpm, enabling the propeller to play its best role. After World War II, high-power medium speed aircraft were gradually used on ships. Marine diesel engine accessories It arranges the cylinders into V shape and adopts reduction gears, which not only greatly reduces the weight of the body, but also helps to improve the efficiency of the propeller. As the medium speed diesel engine body is short, it can reduce the area and height of the engine room, so it is especially suitable for ships with aft engine room and marine ships with engine room under deck.

Through continuous improvement, the diesel power plant is becoming more and more perfect. It has the lowest fuel consumption, can use cheap residual oil, and has high reliability. The overhaul interval is more than 30000 hours, and the thermal efficiency is close to 50%. Therefore, it has become the most widely used marine power plant.

shortcoming

On the contrary, it also has the problem of high pollution - long carbon chain organic compounds are easy to produce suspended particulates (SS) and ultrafine suspended particulates (PM2.5) mainly composed of carbon particles after combustion, plus nitrogen oxides (NOx, which is the main cause of light smoke) under high temperature and high pressure. However, diesel is more stable than gasoline at room temperature and is not easy to burn, so diesel engines are also used in World War II submarines. The use of high quality (ultra-low sulfur) diesel fuel and newer engine and pollution control technologies can reduce a lot of pollution, but until the latest technology can make diesel passenger vehicles meet the environmental standards of the United States and Japan.