Abstract This paper reports experimental and numerical results obtained in a free-vortex gas-solid separator, in which the classic conical-section of the device is replaced by a larger square chamber, where the vortex is free to evolve. An adjustable vortex-limiting plate is introduced at the cross-section in order to allow the inversion of the coherent structure and guarantee a natural vortex length of the swirling flow according to the inlet velocity in the separator. Both single- phase and multiphase flows were analyzed. In the latter case, only very low particle concentrations, between 100 and 500 mg/m3, were considered. Compared to the classic cyclonic separators, the new geometry showed advantages in performance, such as a smaller pressure drop. Moreover, unexpected behavior was observed, since the pressure drop increased by an average of 10% when the particles were injected into the flow at the low concentrations considered.

中文翻译：

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在低颗粒浓度下运行的方形自由涡旋旋风分离器中压降增加的研究

摘要 本文报告了在自由涡流气固分离器中获得的实验和数值结果，其中该装置的经典锥形截面被更大的方形腔室所取代，其中涡流可以自由演化。截面处引入了可调涡流限制板，以允许相干结构反转并根据分离器中的入口速度保证旋流的自然涡流长度。分析了单相流和多相流。在后一种情况下，只考虑了非常低的颗粒浓度，介于 100 和 500 毫克/立方米之间。与经典的旋风分离器相比，新的几何形状在性能上表现出优势，例如更小的压降。此外，还观察到了意想不到的行为，