Abstract We report a systematic experimental study to characterise the isothermal flow-field within a vortex-based solar cavity receiver with an open aperture. Measurements were performed using particle image velocimetry for a fixed flow rate through the inlet jets to achieve Reynolds number of ReD = 11800. A range of flowrates through the outlet were assessed for a fixed inlet flow rate, including that where the total outlet flow significantly exceeds the jet inflow to induce a net inflow through the aperture. Measured results reveal the presence of a central recirculation zone (CRZ) within all configurations considered here, with the strength and position of the CRZ depending on the amount of excess flow through the outlet. The magnitude of mean and root-mean-square velocities was found to be increased within the central region of the vortex receiver for open-aperture cases, while the excess outlet-flow tends to inhibit this increment. The results also show that increasing the excess outlet-flowrate can significantly reduce the flow egress through the aperture, while also increasing the flow ingress through the aperture.

中文翻译：

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具有开放孔径的基于涡流的太阳能腔接收器内的流场

摘要 我们报告了一项系统的实验研究，以表征具有开放孔径的基于涡流的太阳能腔接收器内的等温流场。使用粒子图像测速仪对通过入口射流的固定流速进行测量，以实现 ReD = 11800 的雷诺数。针对固定的入口流速评估通过出口的一系列流速，包括总出口流量显着超过射流流入以引起通过孔的净流入。测量结果表明，在此处考虑的所有配置中都存在中央再循环区 (CRZ)，CRZ 的强度和位置取决于通过出口的过量流量。在开放孔径情况下，涡流接收器的中心区域内的平均和均方根速度的大小被发现增加，而过量的出口流量往往会抑制这种增加。结果还表明，增加多余的出口流量可以显着减少通过孔的流出量，同时也增加通过孔的流入量。