氣流分佈對開放式冷藏櫃均溫性之影響

The effect of air distributions on the uniform temperature at an open type refrigerated display cabinet

戴智雄(Chih-Hsiung Dai)

指導教授 ： 蔡瑞益

中原大學/工學院/機械工程研究所/碩士(2009年)

https://doi.org/10.6840/cycu200900927

摘要

本文中實驗所使用之垂直開放式冷藏櫃，尺寸大小為長0.6公尺、寬0.91公尺、高1.9公尺。利用不同背板開孔分佈，探討開放式冷藏櫃均溫性之較佳化，由結果顯示開放式展示櫃若要有較佳均溫性，背板開孔數量和位置需要與出風氣簾相互搭配。開放式冷藏櫃一般高溫大多位於下層層板，以本文中較佳之背板開孔分佈與原始背板開孔分佈比較，其第四層棚架至第六層棚架內溫度大約都較原始背板開孔分佈低1℃，而第一層至第六層櫃內溫差亦較原始背板分佈小，故整體展示櫃均溫效果較佳。因此若展示櫃能設計足夠風量及適當的背板開孔分佈，加強對於開放式展示櫃下層高溫區之冷卻效應，將可以改善整體展示櫃之均溫性。本文中蒸發溫度增加1℃，對於開放式展示櫃冷藏系統循環性能係數(COP)約改善7.79%。

關鍵字

數值模擬 ； 氣簾 ； 背板開孔 ； 展示櫃

並列摘要

In this paper, the vertical open-type refrigerated display cabinet is used for experimental. The size is 0.6m (L) 0.91 m (W) 1.9 m (H). The present work is to study different porous opening types for back panel flow inlet to sustain the uniformity of temperature distributions inside the display cabinet. The results show that the suitable number and position of back panel pores accompanied with discharging air curtain will reduce the temperature gradient inner the cabinet. Usually, the higher temperature occurs at the lower level. In order to compare the original distribution of back panel pores and the better selected types studied in this case, the temperature of level four to six decreases about 1℃ for the newly design types of back panel porous distribution. The temperature difference between levels one to six becomes smaller than the original design and shows better cooling performance of the whole display cabinet system. Hence, to provide enough flow rate and figure out the suitable back panel porous distribution will enhance the cooling effect for the lower level zone, and improve the temperature sustaining condition. In this paper, for every 1℃ increase in evaporation temperature that can be achieved in display cabinet, the coefficient of performance (COP) of refrigeration system connected to the display cabinet can be improved by 7.79%.

並列關鍵字

perforated back panel ； air curtain ； simulation ； display

參考文獻

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