預測變冰水量冰水機性能之熱力模式的發展與驗證

Development and Verification of a Thermodynamic Model on Chiller Performance with Variable Chilled Water Flowrate

蔣國雄(Kuo-Hsiung Chiang)

指導教授 ： 李宗興

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

工業用冰水主機設計蒸發器的冰水流量都是在固定流量下運轉，但是隨著整體能源使用最佳化考慮，VPF(variable-primary-flow systems)冰水一次側變流量系統對整體能源消耗的減少，將使愈來愈多的空調冰水系統直接改變經過冰水主機蒸發器的冰水流量，使冰水可變流量節能具體化並減少更多的能源消耗（初始成本及運轉成本的減少）。在VPF系統應用中，變冰水量冰水機為了配合負載需求而採用變冰水量的模式來配合卸載，因此需要發展在變冰水量參數下的經驗模式，作為評估變冰水量冰水機應用在VPF不同運轉條件時的性能行為，並提供現場變冰水量冰水主機故障檢測、診斷及性能的改善空間以做系統效率提昇之參考依據。本文將原本應用於固定流量的Gordon-Ng通用冰水機熱力學模式發展成為變冰水量之冰水主機熱力模式並與Gordon-Ng通用冰水機熱力學模式作為冰水機運轉特性之預測模式，再利用穩態運轉特性之冰水機測試數據檢驗上述模式，藉以確立本文所發展新模式之適用性。綜合研究結果發現：創新的變冰水量熱力模式(Model-1)與Gordon-Ng通用冰水機熱力學模式(Model-2)比較，其均方根誤差（RMSE）平均約低於10.1%及相對均方根誤差(R-RMSE)平均也約低於10.4%。比較後證明變冰水量之冰水機熱力模式在此之中的預測能力，是優於前者現有之經驗模式。

關鍵字

變冰水量冰水機 ； C.O.P ； 經驗模式

並列摘要

Design of evaporator chilled water flow rate for industry is based on operation under constant flow rate. Considering the energy efficiency optimization, VPF will reduce the energy consumption and reducing the chilled water through evaporator, and thus energy consumption both in the initial cost and operation cost. In VPF, chiller will unload according to the thermal loading by variable chilled water flow rate. A experimental model is developed to change the parameters and simulate the chiller performance. And the model can be also used as the tool of chiller troubleshooting, diagnosis, and performance improvement.Gordon-Ng thermodynamic model used on constant water flow rate is redeveloped for variable water flow for the chiller characteristics model. The verification of the model is based on the chiller test data at stable state.Both experimental models are verified by statistics R2, RMSE, R-RMSE. Based on the 11 steady state data, it is found the variable water flow rate modified from Gordon-Ng will be worse than Gordon-Ng model, in some circumstances. On the average, the predictive accuracy of variable water flow rate is better, and the Gordon-Ng simplified model is worse. The results can be a reference data for chiller capacity control, performance prediction, energy saving, and troubleshooting.

並列關鍵字

Liquid Chiller ； Coefficient of Performance ； Empirically Based Model

參考文獻

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