| Vehicle heater is an important assistant facility used for cold engine starting, carriage heating and windshield hoarfrost removing, which has good application future both in home and abroad. Vehicle heater research and application started earlier abroad, they have mature technology and abundant products up to now. Compared with them, vehicle heater research began a little later home. From the modeling beginning to now, we already have the ability of developing and manufacturing new heater all by ourselves. Shandong University is in front among other universities in vehicle heater research. Shandong University and Hebei Hongye Mechanical Ltd. cooperate with each other and have developed several types of new vehicle heaters, and what's more , we have got several invention patents and have our own intellectual property rights.The way of traditional new product development is to combine theory with experience. First design and make a muster, then evaluate and improve the technical parameters of the new product by experiments, which is a big cost of time and money. With the development of computer technology, numerical simulation is becoming more and more advanced, which plays more and more important part in various project fields and gives instruction to the improvement of new products. And for the optimization of products which have already been manufactured in batches and in use, numerical simulation also plays an important role. This project was carried out with the CFD software Star-CD to optimize the YJP-Q32 spray atomization vehicle heater of Hebei Hongye Mechanical Ltd. And the simulation results were compared with the experimentation results, too.The whole work of the project can be divided into three parts, namely theory research, numerical simulation and experimentation validation. The theory research part mainly consulted the literature about fuel spray , mixture and combustion together with CFD numerical simulation theory, which can provide theory induction for the after simulation and configuration improvement of the burner. The numerical simulation part consists of three parts, including model creation, simulation and post progress. The geometry model was created by Pro-e software according to the drawings of the heater with some predigestion. And the gridding model was made with the tools of Star-CD. The computational and boundary conditions were determined according to the tutorial of Star-CD. The post progressing mainly carried out compare and analysis of critical parts of the configuration. The main work is about the air flow inside the burner, together with spray and combustion simulation with cone angel of 45,60 and 80 degrees. The experiments were made at test-bed set up by ourselves. The main goal is to compare the heat efficiency and emission of the heater under different work conditions.From the simulation results of air flow inside the burner, it is found that the swirl at the rearward of the heater is too weak, which is disadvantage for the mixture and combustion, as may result in high NO emission. Through analysis of three different cone angel simulation results, a conclusion was got that the cone angel of 80 degrees is the best, with higher combustion temperature and combustion efficiency and without NO and soot emission increase, which is consistent to the experiment results.
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