有機朗肯循環中油分離器之開發與性能分析

Abstract

本研究是要研究油分離器在不同的入口條件下，對整體油分離器效率的影響，工作流體採用HFC-134a，冷凍油使用solest120，冷媒流量範圍為250 g/min~600 g/min，壓力為750~1300 kPa，冷媒過熱度8 ℃~18 ℃，目前可以知道入口的慣性力若超過油分離器的負荷，效率就會開始下降，慣性力越大則效率越低。而改變油分離器的設計也會影響油分離器本身的濾油能力，實驗中，比較了出入口均有三層濾網、僅入口有三層濾網與僅出口有三層濾網共三隻油分離器，可以得到出入口均有濾網的油分離器效率是最高的結果，而剩下兩個油分離器在設計上只是一個擺在入口一個擺在出口，看似設計很像，但實際上在僅出口有三層濾網的效率與能力都是最低的，最後，研究過熱度增加對效率的影響，因為過熱度提高也提高了慣性力，可得過熱度上升效率會下降的結果。

In this study, the separation efficiency of oil separator is examined. The separation device is a mesh-type separator. The mesh contains 39 holes/inch and a total of three types of separator are made and tested. The meshes are placed at the inlet and outlet for standard oil separator while the mesh is placed either at the inlet or outlet only for the other two oil separators. The controlled test conditions of the test ranges are 750-1300 kPa, 250 g/min-600 g/min, and with superheat being 8 - 18℃. Based on the test results, it is found the best separation efficiency occurs for mesh being placed at both inlet and outlet, followed by the inlet only, and the worst separation efficiency occurs for the mesh being placed at the outlet. Moreover, it is found that the separation efficiency decreases with rising flow inertia and inlet superheat. For an flow inertia of 600 g/min operated with mesh placing at the outlet only, the efficiency is as low as 80%. On the other hand, the separation efficiency exceeds 98% for all test conditions with mesh being placed at both inlet and outlet.