Research On Air Distribution And Temperature Uniformity In The Baking Finish Oven Of The Enameled Wire With Extra-wide Hearth

The baking finish oven with extra-wide hearth has the advantages of high production efficiency and large output, however, there are still some problems such as the unreasonable air distribution and uneven temperature distribution along the width direction of the oven in the production process. It is important to study the air distribution and the temperature uniformity in baking finish oven with extra-wide hearth. The baking finish oven with extra-wide hearth with catalytic combustion and circulating flow was studied to improve the air distribution and temperature uniformity. The main research work and conclusions are as follows:(1) The air distribution and thermal balance for a RXHW3600baking finish oven system was calculated. The results show that:the heat released by catalytic combustion can meets the heat demanded for production. Owing to unreasonable air distribution in actual production, large quantity of heat was demanded in form of electrical heating and much heat was carried away by exhaust air, so the air distribution of the baking finish oven must be optimized.(2) An air distribution calculation method for baking finish oven was presented. The air distribution for the baking finish oven and the heat efficiency with different hearth width were calculated with this model. It is found that the heat efficiency has nothing to do with the hearth width when the diameter of the wire keeps unchanged. The heat efficiency increases with the wire diameter increasing. After optimization of air distribution for the RXHW3600baking finish oven, the total energy consumption and electrical heat decrease and the heat efficiency increases from20.37%to24.58%.(3) The temperature distributions in the baking finish oven with different hearth width were studied, and the influencing factors were analyzed too. The result shows that the maximum temperature difference along the width direction is12.8K, which can’t meet the technological requirement that the maximum temperature difference has to be less than 5K. Under the condition of different furnace width, quantity of circulating flow has less effect on temperature uniformity. The smaller the branch air duct spacing is, the better the temperature uniformity along the width direction is. The temperature difference along the width direction increases at first, and then it decreases with the width of the hearth increasing.(4) The baking finish oven with the hearth width of2488mm was conducted to optimize here. The structure parameters of the three baffles in air distribution device and the single baffle in air distribution device were optimized respectively by orthogonal experiment method. The structure parameters of the three baffles in air distribution device contain the space between front-top baffle and bottom baffle, the height and width of the front-top baffle, the height and width of the back-top baffle, the height of the bottom baffle. The structure parameters of the single baffle in air distribution device contain the baffle position、the height and width of the baffle. After optimization, the optimal structure parameters of the three baffles and the single baffle were obtained. Under the two optimum structures, the temperature difference along the width direction is3.49K and3.33K respectively, and the pressure drop is18.17Pa and19.8Pa respectively. Compared with the parameters optimized before, the temperature difference decreases12.41K and12.57K respectively, and the pressure drop decreases13.67Pa and12.04Pa respectively. The parameters optimized meet the technological requirement.