本實驗室初次使用三維粒子圖像測速(2D3C)技術作為此次研究方式。在設備方面，需要具備兩台高解析度相機，以及為了能使相機在傾斜一個角度的狀態下，仍然能拍攝出清晰的畫面，故需使用到移軸鏡頭，有了這兩項關鍵的設備，即可符合沙姆定律，當待測平面、鏡頭平面與相機平面這三個面延長並相交於同一直線時，能獲得整個視野清晰的成像。而Stereoscopic PIV之所以能成功的關鍵在於其校正程序(calibration)，因為相機拍攝的角度並非垂直於代測平面，故需要使用標定版。使用棋盤格陣列校正板(calibration target)進行SPIV 校正，該校正板是用於立體攝像系統之影像校正程序，主要調校測量面和標記物之間的間距。過標定版的校正，能重新構建出一個新的平面，使軟體分析上不會因視角問題造成分析有誤。
實驗部分選用正方體透明腔體進行風洞實驗，利用變頻器將風洞風速保持一致5.2 m s^(-1)，採用PIV 2D2C與PIV 2D3C兩種方式同時拍攝，將資料擷取後做分析與驗證。實驗結果顯示兩者的速度分布、動量通量、紊流強度等趨勢皆為相似，除了因PIV 2D3C多出一垂直速度w，導致在平均的速度總和與紊流強度整體數值會些許高於PIV 2D2C。但以整體來說本次研究確定了使用三維粒子圖像測速(2D3C)技術，應用於腔體內流場測速，數值驗證上與PIV 2D2C相似且趨勢近乎相同。也代表本實驗室在三維粒子圖像測速(2D3C)系統的建置上是成功的，且能夠繼續發展並利用此技術完成其他案例的研究分析。

This is the first time that Stereoscopic Particle Image Velocimetry is used in this study. In terms of equipment, the need to have two high-resolution cameras, and in order to make the camera in the state of tilting an angle, can still shoot a clear picture, so the need to use the Tilt-shift Lens. With these two key devices, you can comply with Scheimpflug Principle, when the plane to be measured, the lens plane and the camera plane of these three surfaces extended and intersected in the same line, to obtain a clear image of the entire field of view. The key to the success of SPIV lies in its calibration process, because the angle of the camera is not perpendicular to the proxy plane, so it is necessary to use the calibration target. The SPIV calibration is performed using the calibration target, which is used in the image calibration process of stereo camera systems to adjust the distance between the measurement plane and the marker. The calibration plate can reconstruct a new plane so that the software analysis will not be wrong due to the angle of view.
In the experimental part, a square transparent cavity is selected for the wind tunnel experiment, and the wind speed is maintained at the same 5.2 m s^(-1) with using a inverter, and PIV 2D2C and PIV 2D3C were used to take pictures at the same time, and the data were taken out for comparison and validation. The experimental results show that the velocity distribution, momentum flux, and turbulence intensity are similar, except that PIV 2D3C has an additional vertical velocity w, resulting in a slightly higher overall value for the mean velocity sum and turbulence intensity than PIV 2D2C. However, in general, this study confirms that the use stereoscopic(2D3C) particle image velocimetry, applied to velocimetry of intrachamber flow fields, is similar to PIV 2D2C in terms of numerical validation and the trend is almost the same. It also represents the success of the stereoscopic particle image velocimetry system in our laboratory and we can continue to develop and utilize this technology for other case studies.

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