本研究設計一個V型射流振盪器，再針對V型射流振盪器引致的自激橫向擺動噴流在有、無同向流的條件下，藉由實驗方法研究噴流的流動與混合特性。使用雷射光頁輔助流場可視化方法記錄噴流衍化過程，透過熱線風速儀量測沿噴流中心軸上的速度、紊流強度以及紊流時間與長度尺度，利用邊緣偵測影像處理技術求得噴流側向擴散度，使用追縱氣體濃度偵測技術量測噴流的混合特性。當噴流在無同向流情況時，在不同的噴流雷諾數範圍內，可識別出四種流場特徵模態：無搖擺、次臨界搖擺、臨界搖擺及超臨界搖擺特徵模態。噴流在超臨界搖擺模態時，瞬間速度的時序圖呈現大振幅的振盪，且振盪訊號疊加大的紊流擾動。在噴流中心軸上之速度與紊流強度的量測結果中，得知噴流在距離出口低於2.4倍噴流出口寬度內，超臨界擺動噴流模態之噴流動量快速地由軸向轉換成橫向。橫向振盪引致大的紊流強度與小的紊流時間與長度尺度，因此，強烈地改善了噴流的混合性能。當噴流在有同向流情況時，在中心噴流與同向流雷諾數的域面上，可識別出出三個流場特徵模態：同向流支配模態、過渡模態以及中心噴流支配模態。其中，中心噴流支配模態引致大的紊流強度與小的紊流時間與長度尺度，因此具有較佳的混合特性。

The flow and mixing characteristics of a self-excited transversely swinging jet induced by a V-shaped fluidic oscillator with and without co-flowing jets were studied experimentally. The evolution processes of the jet flow were recorded by using the laser light-sheet-assisted flow visualization method. The jet spread width was identified by the binary edge detection technique. The velocities, turbulence intensities, as well as the turbulence macro time and length scales in the central axis were measured using a hot-wire anemometer. The time-averaged velocity fields were measure by the particle image velocimetry (PIV). The jet dispersion was detected by the tracer-gas concentration detection technique. For transversely swinging jet without co-flowing jets, four characteristic flow regimes (non-swinging, subcritical swinging, critical swinging, and supercritical swinging jets) were identified within different ranges of central jet Reynolds number. The time-evolving velocities of the supercritical swinging jet presented large oscillation amplitudes imposed by large turbulent fluctuations. The measured results of the axial velocities and turbulence intensities in the central axis revealed that in the supercritical swinging jet flow regime the momentum conversion from axial to transverse direction was rapidly performed in the near field at axial distance less than 2.4 times of jet exit width due to the induced transverse jet oscillations. The transverse oscillations of the swinging jets induced large turbulence intensities and small turbulence macro time and length scales, and hence led to large jet mass dispersion. Therefore, the mixing characteristics of the flow was significantly improved due to large jet mass dispersion. For the transversely swinging jet with co-flowing jets, three characteristic flow regimes (co-flowing jet dominated, transition, and central jet dominated) were identified in the domain of the central and co-flowing jets Reynolds numbers. The central jet dominated flow mode has better mixing characteristics because the jet induced large turbulence intensities and small turbulence macro time and length scales.

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