摘要
为了探究入口结构对旋风分离器内涡核摆动的影响,采用雷诺应力模型(Reynolds stress model,RSM)对两种不同入口结构旋风分离器内旋转流动进行了气相流场的数值模拟。结果表明,切向速度在截面上呈现明显的非轴对称现象,主要表现为等值线分布不对称,零值所在位置与几何中心不重合,零值靠近壁面的一侧,切向速度较大,零值远离壁面的一侧切向速度较小。直切式旋风分离器内部偏心比(|Δr|/D)多在0.025~0.050,而蜗壳式旋风分离器内部偏心比则多在0.000~0.025,偏心程度明显下降。蜗壳式旋风分离器在90~270°截面和180~360°截面上的旋转中心偏移轴线值(|Δx|和|Δy|)的平均值均减小,蜗壳式旋风分离器偏心距(|Δr|)的平均值相对于直切式减小23.5%。
In order to investigate the influence of the inlet structure on the vortex core oscillation in the cyclone separator, Reynolds stress model(RSM) was used to simulate the gas flow of two cyclones with different inlet structures. The results showed that the tangential velocity presents an obvious non-axisymmetric phenomenon in the section, which was mainly characterized by the asymmetrical contour distribution. The position of the zero value did not coincide with the geometric center. The tangential velocity was large when the zero value was close to the side of the wall surface, and when the zero value was away from the wall surface, the tangential velocity was small. The internal eccentricity ratio |Δr|/D of the cyclone separator with tangential inlet was from 0.025 to 0.050, while the value of |Δr|/D of the cyclone with volute inlet was from 0.000 to 0.025, and the degree of the eccentricity was significantly reduced. Compared to the cyclone with tangential inlet, the average value of rational center offset axis values |Δx| and |Δy| of the volute cyclone in the cross section of 90-270°and 180-360°was also decreased. The average value of the eccentricity(|Δr| was reduced by 23.5% for the cyclone with volute inlet in respect to that with tangential inlet.
引文
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