流体质点正负差异旋转试验研究

发布时间：2018-08-01 08:16

【摘要】：本文基于设计合理的流体差异旋转惯性加速度试验装置，以试验中的示踪剂颗粒为研究对象，通过系列室内物理试验，测量并计算了流体微团的运动速度及旋转角速度等一系列详细参数，，并结合理论分析，证明流体微团自身存在差异旋转现象，并进一步从差异旋转惯性力的角度解释了弯道水流或排沙漏斗的悬移质分离现象，主要研究内容和结论如下：（1）通过物理模型试验及分析，得出了流体质点自身存在差异旋转的结论，并且流体质点的运动既不是自由涡也不是强迫涡，它更不属于兰金涡与二次流。（2）通过力学计算并结合理论分析得出，靠近水面的流体质点在运动时，只受离心力与差异旋转惯性力作用，此时离心加速度随质点开始向远离中心的位置运动而增大，向中心聚拢时减小；差异旋转惯性加速度随质点向远离中心的位置运动而增大，当向中心聚拢时运动方向与离心加速度相反，绝对值增大，到质点趋于静止时减小。（3）当流体质点向远离中心的位置扩散时，离心加速度与差异旋转惯性加速度方向相同，质点做离心运动。当向中心聚拢时，若差异旋转惯性加速度的绝对值小于离心加速度，质点做离心运动；反之，若绝对值大于离心加速度，则做向心运动。（4）通过对排沙漏斗模型试验数据进行力学计算，得出流体质点在排沙漏斗的各径向断面同一水平高度上，随着半径的增大，差异旋转惯性加速度的绝对值也不断增大，离心加速度则逐步减小，其差异旋转惯性加速度与离心加速度之比不断加大。（5）根据以上结论对排沙漏斗工程中的水沙分离机理进行理论分析，得出在排沙漏斗中悬移质泥沙正是在负差异旋转加速度的作用下向中心排沙底孔作向心运动，即漏斗内的悬移质泥沙是由于向心惯性力的作用而运动至中心底孔被迅速排走。
[Abstract]:Based on the reasonable design of fluid differential rotation inertial acceleration test device, the tracer particles in the test are taken as the research object, and a series of indoor physical tests are carried out. A series of detailed parameters, such as velocity of motion and angular velocity of rotation, are measured and calculated. Furthermore, the phenomenon of suspended mass separation in bend flow or hourglass bucket is explained from the angle of differential rotational inertia force. The main research contents and conclusions are as follows: (1) through physical model test and analysis, It is concluded that the fluid particle has its own differential rotation, and the motion of the fluid particle is neither a free vortex nor a forced vortex, and it does not belong to the orchid vortex or the secondary flow. (2) through mechanical calculation and theoretical analysis, it is concluded that the motion of the fluid particle is neither a free vortex nor a forced vortex. (2) through mechanical calculation and theoretical analysis, The fluid particle near the water surface is only affected by the centrifugal force and the differential rotational inertia force, and the centrifugal acceleration increases with the particle moving away from the center and decreases when the particle moves toward the center. The differential rotational inertial acceleration increases with the particle moving away from the center. When the center is closed, the direction of motion is opposite to the centrifugal acceleration, and the absolute value increases. (3) when the particle diffuses away from the center, the centrifugal acceleration is the same as the differential rotational inertial acceleration, and the particle moves in a centrifugal motion. If the absolute value of the differential rotational inertia acceleration is less than that of the centrifugal acceleration, the particle moves in a centrifugal motion when the center is closed; conversely, if the absolute value is greater than the centrifugal acceleration, (4) through the mechanical calculation of the model test data of sand discharge funnel, it is concluded that the fluid particle is at the same horizontal height of each radial section of the funnel with the increase of radius. The absolute value of differential rotation inertial acceleration is also increasing, while the centrifugal acceleration is gradually decreasing. The ratio of differential rotational inertial acceleration to centrifugal acceleration is increasing. (5) based on the above conclusions, the mechanism of water and sediment separation in sediment discharge funnel engineering is theoretically analyzed. It is concluded that the suspended sediment in the funnel is moving to the center bottom hole under the negative differential rotation acceleration, that is, the suspended sediment in the funnel moves to the center bottom hole because of the action of the concentric inertia force.
【学位授予单位】：新疆农业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV149

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