Research on temperature uniformity regulation technology of a high and low temperature test chamber

Temperature uniformity is an important indicator to ensure the validity and credibility of the experimental results of the high and low temperature test chamber. The existing studies on the influence of the air distribution of the air outlet of the high and low temperature test chamber on the temperature uniformity are mainly through simulation technology, and all ignore the influence of the uneven width of the air duct of the test chamber on the overall temperature uniformity of the test chamber. By comparing the temperature uniformity, regulation complexity and energy consumption of the equipment, three different temperature uniformity regulation technologies are experimented in the high and low temperature test chamber with an inner chamber volume of 1 000 L, namely regulation louver, hot gas defrosting, and bilateral inlet evaporator. The results show that the bilateral inlet evaporator technology is more beneficial to the internal heat exchange of the air duct of the equipment, which can effectively eliminate the influence of the uneven temperature of the air duct of the test chamber on the experimental results, and the temperature uniformity of the test chamber under different wind speeds is tested in the same test chamber with three air outlet shapes (square, round and diamond) respectively. The results show that the wind speed has a great influence on the environmental test chamber, and the higher the wind speed, the better the temperature uniformity of the test chamber. When the wind speed is the same, the shape of the air outlet has a great influence on the temperature uniformity of the test chamber under high temperature conditions, and the temperature uniformity of the square air outlet is the best. Under normal and low temperature conditions, the shape of the air outlet has little effect on the temperature uniformity of the test chamber.