並聯式儲冰空調系統一次側二次側冰水等流量實驗探討與效益分析

Experimental Investigation and Performance Analysis of Parallel Ice-Storage Airconditioning System with Equal Primary / Secondary Chilled Water Flow

許智凱(Chih-Kai Hsu)

指導教授 ： 李文興

國立臺北科技大學/機電學院/冷凍空調工程系所/碩士(2005年)

摘要

以往儲冰系統利用儲冰優先、主機優先、等比例等模式融冰，往往忽略冰水主機及其它相關設備的運轉效率，使系統耗電量增加，經濟效益不佳。而一次側/二次側變流量冰水系統的運轉，二側流量無法與一次側流量保持相等，必需利用共通管旁通部份冰水，造成泵浦能源的浪費。本研究將融冰板式熱交換器置於一次側與冰水主機並聯，一次側冰水泵使用變頻運轉，其作用相當於一台變流量的冰水主機，保持一次側與二次側冰水流量相同，使冰水主機及其相關附屬設備維持高效率運轉，並節省融冰泵的耗電。
以一醫院空調負載案例進行實驗研究分析，當二次側冰水流量變化，影響二次側出水溫度時，利用變頻板熱泵調節流量，可使一次、二次側的流量達到平衡狀態，而控制板式熱交換器出口溫度的滷水泵不會因為一次側水量的改變而造成溫度追逐現象。由於使用變流量融冰模式可使混水現象消除，冰水主機在滿載下運轉，冰水主機及附屬設備之總耗電量較定流量模式還省能，且變流量模式的釋冰用量比定流量模式還來的少，其釋冰效益比定流量模式大，經由數值模擬分析顯示，在所分析的案例中一次側冰水變流量模式較定流量模式全年可節省54370度電，七月份可省19568度電，一月份可省43962度電。
本研究的結果對於儲冰空調系統的設計具有創新的思考，經由實驗証明具有良好效益。在後續的研究上，建議進行運轉策略的研究，以達最佳化運轉的目標。

關鍵字

儲冰式空調系統 ； 變流量 ； 運轉策略

並列摘要

The conventional discharge models of TES system used storage-priority, chiller-priority, and constant-proportion control. These control modes couldn’t consider the overall efficiency of chiller plant. Chillers and their auxiliary equipments were not running at full load of high efficiency. At primary/secondary variable chilled water piping system operating, the primary flow could not keep equal to the secondary flow. We used the common pipe bypassing the exceeded flow. This method is wasting the chilled pump pumping energy. In this study, we address a new idea that used the plant heat exchange of the TES system as a variable flow chiller. By chilled pump variable flow running, keep the primary flow equal to the secondary flow. Then we can save the chilled pump running cost and keep the chillers and their auxiliary equipments high efficiency.
This paper further explicate with a case of a hospital by research and analyze. When secondary chilled water flow was changed to affect secondary discharge temperature. The variable frequency exchanger pump adjust flow make water temperature back to the set point. Primary / secondary flow reaches the balance state. Glycol pump control exchanger discharge temperature will not cause surge because of change of the water flow. The variable water volume (VWV) ice-melting model can enable mixing water to dispel. Chillers and their auxiliary equipments total power consumption fewer than constant water volume (CWV) ice-melting model. One year can save 543470kWH . Can save 19568kWH in July, can save 43962kWH in January.
The result of this study provided the innovative design conception of the TES air conditioning. Via the experiment prove, we get the good benefit. Propose studying operation strategy , reach the goal that the optimization operates .

並列關鍵字

Ice-Storage Air-Conditioning System ； variable water volume ； operation strategy

參考文獻

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