Modeling Of Heat Transfer Performance And Air Pressure Drop Based On Test And Research On Optimization Design For The Tube And Corrugated Fin Radiator

Vehicle radiator is an important part of the automobile cooling system. Its regulating ability has direct impact on power, economy and reliability of the engine. Under the condition of enough heat transfer performance, the radiator with smaller volume, lower quality and higher efficiency has become the goal of heat radiator design. During the process of developing the compact and efficient cooling system, the design and optimization of radiator module is one of the most important research content. To provide an efficient and accurate guidance means to theoretical calculation and design for the tube and corrugated fin radiator, this paper has used both experimental and theoretical methods to study the design, check, optimization and parametric and cooling fluid properties of the tube and corrugated fin radiator. The main contents of this paper include:By means of the wind tunnel test technology, the heat dissipation and the wind resistance and the water resistance and the air outlet temperature and the liquid outlet temperature of three models of the radiators using water as coolant, respectively in the20point, have been researched. On the basis of analysis, the test results show that the heat dissipation of the water side and the gas side of the radiator both improve with the wind velocity or water flow increasing, otherwise reduced. The heat dissipation along the wind direction has a greater extent than along the water flow direction. The air side resistance of radiator has been almost entirely decided by the velocity of the air. The air speed increases, then resistance increases. On the other hand, with the decrease of wind speed, wind resistance also decreased. For the same wind speed, no matter how water flow changes, the wind resistance is almost not affected. The value of the water side resistance of radiator almost entirely depends on the water flow of radiator. The larger the value of water flow, the higher the water side resistance. Otherwise, the water side resistance is smaller. With the same water flow the wind speed almost has no effect on the water side resistance of radiator.According to the theoretical analysis and the test data obtained from the wind tunnel test system, by the method of multiple linear regression analysis, the heat transfer and flow resistance forecast model of the tube and corrugated fin radiator has been constructed. And the general correlation (correlation of heat transfer factor J, friction factor f and Reynolds number) of heat transfer and flow resistance for manufacturers has been achieved. This model has been applied to the calculation software. By the simulation, we found that the error between the simulation result and the experimental value has been greatly reduced, which has greatly improved the accuracy. The forecast model applied to the theoretical of the radiator calculation is feasible.During the process of constructing the model, water which is used as coolant has been researched. However, realistically coolant is usually composed of water and antifreeze. For more in-depth understanding of the performance of coolant added antifreeze, this article has also carried on the wind tunnel test of ethylene glycol and propylene glycol in the wind tunnel test rig rebuilt. The results show that being compared with the pure water as the coolant, heat dissipating capacity of propylene glycol coolant and ethylene glycol coolant will reduce, and the water side flow resistance of propylene glycol coolant and ethylene glycol coolant will increase, and the gas side flow resistance of propylene glycol coolant and ethylene glycol coolant is consistent. At the same time the simulation calculation of ethylene glycol and propylene glycol by use of software has been carried on. The results show that the software simulation results agree well with the experimental results, which means that the built model is also applicable to other types of cooling liquid.In order to shorten the design period of the radiator of automobile radiator manufacturers and improve the design efficiency, the design and checking calculation software of the tube and corrugated fin radiator is programmed by VB6.0. Because the use of genetic algorithm is not affected by the search space restriction hypothesis and does not require the object function is continuous, differentiable and single-peak. At the same time, considering the characteristics of the radiator itself, the improved genetic algorithm has been applied to the optimization design of the tube and corrugated fin radiator. In order to meet the requirements of the heat transfer and flow resistance, the structure parameters optimization scheme of the radiator core body has been present to reduce the heat dissipation area and material. In order to improve the efficiency of design drawing, by means of3-D graphics software as design platform, the parametric design of the radiator has been completed with VB language. Eventually, the paper has formed the whole software which contains design, check, optimization and parameterization for the tube and corrugated fin radiator.