Numerical Study Of Coolant Flow In Engine Block Water Jacket

The affection of the coolant flow in engine's cooling system focus on the cooling effective, heat load of the parts, the distribution and usage of heat energy. Meanwhile, the emissions of the engine are closely related to the coolant temperature. With the approaches to increase output power used, perfectly improving cooling system have become the important tasks to design original engines. Because of the complexity of the water jacket, the measurement study was difficult to observe the practical flow conditions in jacket and limit to comparing and analyzing the temperature and flux. For this reason, the numerical simulation on the flow and heat transfer in engine water jacket becomes a principal method to optimum cooling system.From the existing publishes on the simulation of coolant flow, it was discovered that these achievements are not effectively to solve the engineering problems. In this dissertation, it was analyzed the latest development and application of turbulent models. The turbulent model V2F was found to be the most novel and accurate for simulating the coolant flow in engine water jacket. The 3-D geometry of the engine block water jacket for type 6110 diesel engine, including the oil intercooler, was built by Pro/Engineer. In order to account for the affection of outlet location on coolant flow, the simplified cylinder head water jacket was also attached to the geometry above. The current computational mesh generating techniques were clearly reviewed. 1.4 million grids was constructed with fine near-wall mesh and local refinements. Heat transfer boundaries and several other critical parameters were discussed and defined. Important numerical results, such as velocity distribution and heat transfer coefficient, were analyzed in detail. Flaws of the water jacket and the causes were presented. The suggestions further optimizing water jacket were proposed.Major causes of disparity in the numerical simulation for water jacket was analyzed, general simulation methods are incapable to describe near-wall flow accurately. The turbulent model V2F was found to be effective to predict near-wall flow and more suitable to simulate the complex flow and heat transfer in water jacket. Compared with k-ε model, the turbulent model V2F was firstly applied to simulate engine coolant flow in this dissertation.