Multi-dimensional Numerical Simulation Study On Spray Of Low-quality Diesel

Marine diesel engine using low-quality oil is aimed at rational using oil resources and reducing operating costs. But the physical and chemical properties of heavy oil are much worse than diesel. So, the pretreatment of heavy oil before using is very important. Pre-warming is one of the effective measures. For the internal combustion engine, the spray is very important. The quality of atomization determines the quality of the formation of flammable mixture, which affects the combustion, and ultimately will affect the dynamics, economy and emission of internal combustion engines. Therefore organize the fuel spray will play a decisive role to the indicators of the IC-engine. And the quality of the spray will be more important when using heavy oil.After comprehensive analyzing the mechanism of current research in the IC-engine fuel injection atomization and research results, establish a suitable mathematical physics model. Simulate the spray of 20# heavy diesel by Multi-dimensional numerical model.Cavitating flow plays a vital role in atomization. Taking account flipped will not happen in real live. By changing the geometry of nozzle control the flow in the nozzle, discuss the spray in single-phase flow and cavitating flow respectively. Calculate the change of the physicochemical parameters of 20# heavy oil with the change of temperature. Study the spray of 20# heavy oil in different injection pressure, nozzle diameter and pre-warming temperature.Research shows that cavitating flow play a positive role to the spray. Compared to single-phase flow, it will get longer penetration, smaller SMD and so on. It will get longer penetration and smaller SMD when raising injection pressure. Pre-warming plays a positive role in spray. It improves the atomization quality of the 20# heavy diesel.