微型渦輪機廢熱驅動之吸收式冷凍系統性能分析與測試研究

Performance analysis of Absorption Refrigeration System using Microturbine Exhaust Heat

葉憲錡

指導教授 ： 蔣小偉

國立清華大學/工學院/動力機械工程學系/碩士(2014年)

摘要

本研究是引進分散式發電及廢熱回收的設計概念，利用改良後之Jet公司的SPT5微型渦輪引擎(Microturbine)為基礎進行系統的分析，該發電系統在全轉速時發電量可達14kW、效率亦達10%以上，並利用其運轉時會排放高溫廢熱(500~700°C)的特性結合吸收式冷凍空調(Absorption Refrigeration System ,ARS)，將能同時達成發電及製冷輸出，並大幅提升燃料的使用率，減少能源的損耗。
本研究主要針對微型渦輪機及ARS及複合系統三部分進行分析，首先建立起包含發電量、效率、排熱等參數的微型渦輪機性能曲線，再利用程式建立單、雙效應之ARS模型，進行參數分析歸納出各站位溫度對系統性能係數的影響並搭配擴散吸收式冷凍系統的實驗作進一步驗證與參數最佳化；最後分析複合系統在不同渦輪機轉速下之性能並作環境的分析。
由研究結果可知，單、雙效應的系統能輸出14.4kW的發電量並分別可產生40及80kW的製冷功率，其各自的燃料使用率亦高達37及70%，在許多國家中已極具競爭力。上述結果將可提供後續在高潔淨電力及能源回收之複合系統研究上之參考依據。

關鍵字

微型渦輪機 ； 吸收式冷凍系統

並列摘要

Distributed power generation is a current trend. Our lab has demonstrated that microturbines can be of high efficiency, light weight, compact, and mobile. On the other hand, the absorption refrigeration system (ARS) can use exhaust heat as input. Using a waste heat driven generator to replace the conventional compressor, the ARS can be a great energy saver with low capital cost, low noise, and no electricity input to drive the compressor.

In this study, we used a microturbine (SPT5 model made by JETCAT) as the main power source for our system. The microturbine has attained a thermal to electric efficiency of 10% with about 700-1000K exhaust gas temperature. Then we would build the simulation program of single and double effect ARS and analyze the Coefficients of Performance(COP) and temperatures in both ARS systems. With these data, we can perform a study of the configuration design and performance analysis of the system. Finally, the feasibility of this system would be analyzed.

In conclusion, by using the concept of waste heat recovery, the overall efficiency of the system can be greatly improved. With this configuration, it can provide an electricity load of 14.4 kW, a cooling load of 80 kW, and the fuel usability of the system can be about 70%. Finally, the analysis simulation system for a GT-ARS system is completed. This system can provide future references in high efficiency and clean environment with heat recovery system.

參考文獻

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