| In the future, high power density engine will be a major industry direction of the internal combustion engine development. Power density improvement directly resulted in the engine heat load condition deteriorated. Therefore, the new cooling system designation method, the cooling heat transfer performance optimization, the new high-speed engine cooling water pump researches achieved more and more industry attention. Meanwhile, domestic engine with more stringent emissions regulations, engine oil crankcase ventilation system consumes problems were more concerned, the new design method of oil and gas separator is gradually applied to various types of internal combustion engines. The EGR system is a fine way to reduce NOx emissions from internal combustion engines. As an important technical means of EGR system, the design of EGR cooler is imperative.In this paper, based on CFD simulation and experimental techniques, the liquid heat transfer and gas-fluid separation problems of internal combustion engines were carried out in a detailed study, and obtained a significant research results.Take a certain diesel engine car for example, a fluid-structure interaction model of a certain type of engine cooling water jacket boiling heat transfer mode was established.The machine cooling water jacket temperature field, pressure field, velocity field were studied and flow distribution through the holes between the head and the body of the engine were optimized. Critical data experiments were used to verify the accuracy of this model. And then the results of the internal combustion engine cooling water jacket were used, to analysis the cylinder head temperature field. Compare the data of experiments and simulations of the nose-zone temperature, which proved the accuracy of the model.By CFD simulation methods, we studied the relationship between the tip clearance and the key performance indicators of the high speed engine pump. Adopt the tip clearance engine optimization methods to design a certain type of high-speed pump. Compare the experiment results between the new designed sample water pump and original water pump verified that, overall performance was significantly improved, which proved that Sample pump raw water pump new design and comparative experiment results show that the new pumps significantly improve overall performance, proved that top speed pump gap optimization method proposed in this paper has a great value in engineering.Detailed studies were undertaken on the relationship between the lubricating oil consumption and engine speed, load on a certain type of diesel, the crankcase ventilation system research concerned blow-by gas flow and engine oil content. Utilizing the DPM model, taking the experimental data as boundary conditions, the flow field of a labyrinth oil mist separator was achieved, and the separation efficiency was also achieved by statistical. After that, a variety of labyrinth oil separators were designed, then the optimal solution was selected out, conducted out some sample production, and finally tested in some experiments. The experiment showed results indicated that the oil consumption was reduced to50%, using the new design of the oil separators, compared with the original oil separator, while the crankcase ventilation system pressure and flow changes was not very obvious.We made an innovation and invention of the EGR cooler test and analysis system. Not only heat transfer performance can be tested, but also thermal shock, coke experiment can be carried out. Based on this system, combined with CFD simulation tools, a detailed analysis of experiments and simulations were made to find out the relationship of two typical EGR cooler systems involved various performance parameters, thus obtained some novel results and conclusions, the valuable data would fill the gap for design and development of the EGR cooler. |
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