氣泡沿傾斜邊界運動之研究: 利用雷射發光之PTV量測與無網格數值方法之模擬

Flow due to bubble motion along an incline: Laser-illuminated PTV measurements and meshless computations

文向權(Hsiang-Chuan Wen)

指導教授 ： 卡艾瑋

國立臺灣大學/工學院/土木工程學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.01558

摘要

本研究著重於與液體分離之氣泡運動和吸引周圍液體之流場分析。氣泡穩定地沿著傾斜之緩波運動。實驗與數值方法均會在文中提及。小規模的實驗也會利用兩種黏度不同之液體加以進行。數位影像則是利用雷射激發光芒的顆粒當成追蹤物去進行可視化與量測之工作。文中將會介紹經由組合一連串從攝影機擷取出的影像成為一個複合的流場圖去模擬長時間曝光的照片。數值模擬方法包含了一連串不連續之點源與渦旋並且靠著從實驗中獲的之氣泡形狀與分離點進行模擬。

關鍵字

流場分析 ； 氣泡 ； 無網格數值模擬 ； PTV ； 雷射發光顆粒

並列摘要

The present investigation focuses on the motion of an isolated air bubble and the induced ambient flow. The bubble moves steadily along an incline of mild slope. Both experiments and computations are performed. Small-scale experiments are conducted with liquids of two different viscosities. Digital imaging of laser-illuminated tracers is used to visualize and measure the flow. A composite picture of the flow field is obtained by assembling a sequence of video images in a manner which simulates a long exposure photograph. Computations involve discrete sources and vortices, and rely on the bubble shape and detachment point extracted from the experimental observations.

並列關鍵字

Method of fundamental solutions. ； PTV ； Laser- illuminated tracers ； Air bubbles

參考文獻

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