本研究旨在探討固體結構在微流體裝置中，應用誘導聲流效應於微流道的熱傳分析。實驗使用的微流道以PDMS材質製作，固體結構位於流道兩側壁面，而加熱器放置於流道底部。整體實驗裝置透過ANSYS模擬與實驗相互比對，於相同加熱條件下，調整實驗架設而成功將前人實驗的熱損估算從89 %降至44 %。本研究以壓電片來驅動固體結構而產生誘導聲流效應，選用固體結構將能改善使用氣泡於誘導聲流效應時氣泡容易膨脹的問題。實驗時將直徑3.2 m的螢光粒子與去離子水配成工作流體，搭配可視化、微粒子影像測速法可量測出微流道內之流線圖與全域性速度場；以Rubpy螢光溫度感測塗料與去離子水配成0.07 %的工作流體，搭配TSP溫度量測技術進行微流道之溫度場與熱傳分析。實驗量測包括單邊單結構在有/無主流的誘導聲流效應和交錯式結構之速度場與溫度場分析。單結構有主流下，不同結構與流道的長度比(0.2和0.4)有不同的影響結果：長度比0.2的單結構於雷諾數4時，誘導聲流效應的影響範圍為結構下游約100 micrometer；而長度比0.4的單結構在雷諾數2、4和6時，其誘導聲流效應的影響範圍則分別140、192和75 micrometer。長度比0.2的交錯式結構於雷諾數2、4和6時，皆有越往下游處誘導聲流效應越明顯的趨勢；長度比0.4的交錯式結構則無往下游處誘導聲流效應有延續且放大的趨勢，此現象與可視化的流線圖相互呼應。
本研究最後討論誘導聲流效應於不同結構長度比(0.2和0.4)在不同雷諾數(Re=2、4和6)時的熱傳分析。在定熱通量0.2 W/mm2的加熱條件下，比較有/無誘導聲流效應下流體實際帶走的熱量增益。不論是長度比0.2或0.4的結構長度，在誘導聲流效應下皆能提高流道入出口溫差。透過TSP量測出的液溫等溫線圖，可以發現在誘導聲流效應下整體等溫線會往上游平移，且隨著交錯式結構的設計，越往下游等溫線提前發生的情況越明顯。最後發現長度比0.2的結構長度在雷諾數4時有最大的熱傳增益，推測為在此雷諾數下能更有效地使誘導聲流效應透過交錯式結構而延續且放大，整體熱傳增益達22.53 %。觀察此條件下沿著軸向不同截面的有/無誘導聲流效應的液體溫度，可以發現越往下游流體溫度差別越大，與速度場之越往下游誘導聲流效應越明顯相符。

This study aims to investigate acoustic streaming effect on heat transfer enhancement in microchannel flow by using staggered structures. The microchannel devices were made of PDMS material, with staggered structures were positioned on the side wall of microchannel. Microheaters were fabricated by using MEMS technology and placed at the bottom of the microchannel to provide constant heat flux thermal boundary condition. After investigation of heat loss in the microchannel experiment with ANSYS simulation and experiment, the experimental arrangement was adjusted by expanding the PDMS bulk and the heat loss was successfully reduced from 89 % to 44 %. In this study, the structures were positioned at the side wall and they were driven by piezoelectric actuators to introduce acoustic streaming. The using of the solid structures would resolve the problem of acoustic straming with air bubbles, which could be easily expanded during the acoustic streaming. For the velocity experiments and flow visualization, red fluorescent particles of 3.2 micrometer diameter were seeded into deionized water to be used as tracker particles. The velocity profiles inside the microchannel devices were successfully obtained by Micro-Particle-Image-Velocimetry (Micro-PIV) technique. For the temperature field experiment, luminescence sensor of Rubpy was dissolved in DI water as working fluid for temperature measurements. The temperature field and heat transfer analysis were successfully obtained by Temperature Sensitive Paint (TSP) technique. In this study, the velocity profiles and temperature fields have been successfully acquired with single structure and staggered structures with different aspect ratios (a=0.2 and a=0.4) of structure length and channel width as well as different Reynolds number (Re) conditions. From the experimental results of velocity profiles, it can be seen that microchannel flow with staggered structures of a=0.2 can show the effect of acoustic streaming and it can be propogated downstram at Re number of 2, 4 and 6. However, the results of microchannel flow with staggered structures of a=0.4 is different and the effect has been suppressed due to the narrow pathway for the main flow.
Comparing the heat transfer enhancement with acoustic streaming under the constant heat flux (0.2 W/mm2) thermal boundary condition, both microchannel devices with staggered structure designs of a=0.2 and a=0.4 could increase the fluid temperature at microchannel outlet. It could be seen that the staggered structures of a=0.2 has the highest heat transfer enhancement at Re number of 4, with the enthalpy increament up to 22.53 %. It could be found that there were greater temperature differences along downstream with the effect of acoustic streaming, which was similar to the observation of velocity experiments.

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