Numerical Study on the Cooling Effect of Different Inner and Outer jet Velocities for Display Cabinet with Double Air Curtains

• Main Authors: Wei-Chieh Huang, 黃偉傑
• Other Authors: Hong-Sen Kou
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/28005966530537963225

碩士 === 大同大學 === 機械工程學系(所) === 97 === This research focuses on the numerical simulation of an open type vertical display cabinet with double air curtains. The velocities of inner and outer air curtains are separately divided into five conditions for comparison and those are 0.3m/s, 0.6 m/s, 0.9 m/s, 1.2 m/s, and 1.5 m/s. This work introduces the temperature index of display cabinet, cold air leakage, cooling capacity, and CPI (cabinet performance index) to check the effect of this display cabinet and then to find its optimum operating conditions. The software package of PHOENICS was used to simulate the flow field of this 2-D display cabinet. Standard k-ε turbulence model was used in simulation. According to the foregoing method and numerous simulate results, here can find 1. In all situations, the cooling capacity and function of the display cabinet due to single air curtain is worse than that of double air curtains. 2. Considering the temperature distribution of the display cabinet and total energy consumption in all five types of situations, the best collocations of velocity on inner(outer) air curtain are set as 0.3 m/s(0.3 m/s), 0.6 m/s(0.5 m/s), 0.9 m/s(0.7 m/s), 1.2(0.7m/s), and 1.5(0.9m/s), respectively, where the average temperature of display cabinet can be keep on 6.5℃、4.2℃、3.2℃、3.0℃、2.5℃, and the energy consumption are 444 W/m, 648 W/m, 780 W/m, 910.4 W/m, and 1064.6 W/m, respectively. 3. Focusing on the cooling effect, the best collocation between inner and outer curtain velocity are 0.3 m/s(1.5m/s), 0.6 m/s(1.5 m/s), 0.9 m/s(1.5 m/s), 1.2 m/s(1.5 m/s), 1.5 m/s(1.5m/s), where the value of cooling effect are 2964 W/m, 4666 W/m, 6229 W/m, 7790 W/m, 9398 W/m, respectively. 4. For the magnitude of cooling capacity, it only represents the cooling capability of the whole display cabinet in steady state. The larger value it is, the great cooling effect would be get. However, it will also cause the temperature raising immediately.