Research on Flow Field Characteristics of an Artificial Seawater Spray Chamber

人工海水霧化室流場特性研究

李良才(Liang-Cai Li) ； 殷越(Yue Yin) ； 萬博(Bo Wan) ； 欒一剛(Yi-Gang Luan)

《中國機械工程學刊》 42卷1期 (2021/02) Pp. 43-50

摘要

Air-intake filters can filter out salt aerosols in the ocean atmosphere, which plays a key role in improving quality of air intake for marine gas turbine. To carry out precise experiment study on air-intake filters for gas turbine and its improved design, ocean atmosphere simulating in laboratory conditions is needed. Thus, an artificial seawater spray chamber with spraying nozzles is designed to produce aerosols, which is similar to salt aerosols in real ocean atmosphere. Droplet concentration uniformity is an important indicator to measure performance of artificial seawater spray chamber. In this article, experimental method and CFD technology were both used to explore impact of nozzle performance and arrangement on droplet concentration uniformity in the spray field. To obtain more accurate numerical simulation data, an experiment was carried out before simulation to measure atomizer angle and particle size distribution of the spray, which will be used in real artificial seawater spray chamber. Experiment data was taken into CFD software, set as the initial boundary conditions. In the numerical simulation, changing number and arrangement of nozzles, gas-particle two-phase flow field in different schemes have been calculated. Those data can be used as references in designing real artificial seawater spray chamber.

關鍵字

nozzle experiment ； spray chamber ； numerical simulation

並列摘要

進氣濾清器在燃氣輪機中有著極其重要的位置，而噴霧條件又影響著其設計可靠性。因此，為了更好的對燃氣輪機進氣濾清器進行研究和設計，需要按照實際需求為其設計某種形式的人工海水霧化室，以便模擬海洋大氣環境。在人工海水霧化室中，噴嘴為後續霧化提供了必要初始條件，霧化場的均勻性與噴嘴類型、數量、佈置位置等參數密切相關。霧化室的設計通常是基於實心圓錐噴嘴技術。通過一定的方式及規律佈置噴嘴，並結合與之相配的霧化室機構就可以設計出滿足一定需要的霧化室。人工海水霧化室一般需要滿足液滴霧化後霧滴均勻性的要求。在計算流體力學技術迅速發展的今天，通過通用的CFD軟體，結合一定的試驗資料，對霧化立場進行整體模擬計算，可以為整個霧化室的設計提供較為可靠的依據。本文將先利用PDA技術，對噴嘴性能進行試驗研究，得到相關的實驗資料。然後建立霧化室幾何模型，並將得到的噴嘴資料帶入邊界條件進行計算，對設計的霧化室進行研究並優化。