- 學位論文
雙蒸發器之蒸氣壓縮循環應用於電子散熱的可行性分析
Analysis on Feasibility of Applying Vapor Compression Cycle of Dual-Evaporator to Electronic Cooling
摘要
本研究主要探討雙蒸發器之蒸氣壓縮循環系統於電子散熱中，不同CPU負載對整體散熱效能之影響。實驗首先設置一套雙蒸發器之蒸氣壓縮循環系統，藉由冷媒填充量實驗尋找系統適用的最佳冷媒填充量；其二，分析雙蒸發器在穩定的相同負載下對於系統的效能影響，並探討冷凝器通風量與壓縮機轉速對系統造成散熱效能；其三，探討蒸發溫度對系統的結露情形及散熱影響，並根據熱負荷的不同尋找最佳轉速；最後根據最佳轉速所得之結果進行總負載不變而雙邊負載不同對系統造成的散熱結果，再以相關理論與實驗結果進行比較，以得知此系統的效能及可行性分析。實驗結果顯示，當系統冷媒填充量最佳值為250g，雙邊負載各為250W時，有最高COP值為9.6。在穩定負載實驗中發現，當蒸發溫度為19℃時在各結果評比中都有較佳的表現，且在壓縮機變轉速實驗中可得知維持其蒸發溫度可以減少系統結露的產生，並依照總負載不同尋找其最佳轉速以達到節能的效果，而根據其負載所對應的最佳轉速下進行變動負載實驗，結果顯示在總負載為560W的狀態下依然可以使CPU表面溫度維持在70℃以下。由實驗結果可得知在面對多點熱源時，本研究所架設的雙蒸發器之蒸氣壓縮循環可以同時且穩定的對雙熱源進行散熱，並維持CPU溫度在一穩定溫度下。
並列摘要
This research is mainly to discuss the impact of different CPU loads on the overall cooling effectiveness of vapor compression cycle of dual-evaporator in electronic cooling. In the experiment, firstly, a vapor compression cycle system of dual-evaporator is established, and then the applicable optimal coolant filling volume for the system through the coolant filling volume experiment can be found out; secondly, the impact of dual-evaporator with the same stable load on the system efficiency is analyzed and the cooling effectiveness of air volume of condenser and compressor speed for the system is discussed; thirdly, the impact of evaporating temperature on the dew formation and cooling is discussed , and the optimal rotating speed based on different thermal loads is found out; finally，the system efficiency and feasibility analysis can be know from the cooling result of the system caused by the same total load but different bilateral loads based on the optimal rotating speed and the comparison to the experiment results by the use of related theories. As shown in the experiment results, when the optimal filling volume of system coolant is 250g and the bilateral load is 250W for each, the highest COP value is 9.6. It is found from the steady load experiment that, when the evaporating temperature is 19℃, the result has a better performance in the comparison. It can also be known from the compressor variable speed experiment that the maintenance of evaporating temperature can reduce the occurrence of system dew, and the optimal rotating speed can be found out based on different total loads so as to achieve the energy conservation . However, from the variable load experiment at the optimal rotating speed corresponding to its load, the result shows that the CPU surface temperature can still be maintained blow 70℃ under the total load of 560W. It can be known from the experiment results that, vapor compression cycle of dual-evaporator can give out the double thermal sources simultaneously and stably and maintain the CPU temperature at a stable temperature confronting with the multi-point thermal source.