The Experimental And Numerical Simulation Research On The Use Of Heavy Fuel Oil In Medium Speed Diesel Engine

As a production of conventional fossil fuel, diesel fuel resource is becoming shorter and shorter in reserve. Consumption of diesel fuel has brought huge pressure on the economy development of many countries. Diesel being used all over the world is becoming wider in distillate composition and heavier in fuel quality. Thereinto, the heavier quality in fuel can bring better use of current petroleum resource.At present, heavy fuel has been widely used in the low speed marine diesel engines as well as many medium speed diesel engines. Because of much difference in physical and chemical characteristic compared with light diesel oil, heavy diesel fuel makes many problems in fuel combustion on those engines. Many combustion problems could be solved by large numbers of test researches and practice experiences. Even though, there are many further researches needed for the study of combustion performance of heavy diesel fuel in cylinder on large diesel engines.In this paper, combustion performance of heavy diesel fuel in cylinder has been researched by a series of combustion experiments on a certain type medium speed engine. The influence of nozzle parameters and fuel temperature on the combustion performance and economy of heavy diesel fuel has been researched by studying the experiments and simulation of original engine.The results show that:using of heavy diesel fuel causes higher pressure increasing rate during rapid burning period and increased peak pressure under low and medium load conditions; on the contrary, under high load condition, the injection and combustion progress are largely influenced by the performance of injection nozzle, and pressure increasing rate as well as peak pressure could be lower than those in the case of using light diesel fuel.Through the research, the conclusion can be gained as follow:first, increasing the overall pass area can reduce the influence of high viscidity.when using heavy fuel oil on medium speed diesel engine, to increase the power performance. Second, good power performance and economy performance can be obtained when the fuel temperature keeps around 70℃.