基于气旋流的流量放大的悬浮单元的研究

发布时间：2018-04-04 07:26

本文选题：气旋流　切入点：非接触悬浮传送　出处：《浙江大学》2017年硕士论文

【摘要】：本课题研究了一种具有流量放大功能的新型空气悬浮单元:气旋流悬浮单元。气旋流悬浮单元利用高速旋转气流所产生的负压吸入额外的空气,从而能够大幅降低耗气量,在玻璃基板非接触悬浮传送的应用上可带来相当可观的节能效果。目前,气旋流悬浮单元的相关研究仍处于初期阶段,因此,深入了解其流场结构和流量放大特性、明确流量放大的内在机理对于今后的优化设计和应用开发而言至关重要。首先,我们通过实验研究详细分析了气旋流悬浮单元的排气缝隙处的压力分布,指出压力分布曲线与流场之间的联系,以及吸入孔对悬浮单元流场的影响。接着,我们研究了缝隙高度和供给流量对悬浮单元流场、压力场和吸入流量的影响。此外,我们还利用流体数值仿真(CFD)来讨论了圆柱腔内和缝隙处的流线,速度场和压力分布情况,明确了气旋流悬浮单元实现流量放大的基本原理以及吸入孔对悬浮单元各区域的影响。基于上述的实验数据和流体数值仿真的工作,我们简化了Navier-Stokes方程,并结合角动量守恒和近壁面经验模型,提出了气旋流悬浮单元的流场的数学模型。与实验结果进行对比后可知,该数学模型能很好地再现缝隙的速度分布,压力分布形状和吸入流量曲线的趋势;因为忽略了气流在竖直方向的流动、上下壁面的阻力等因素,所以最终积分得到的压力数据和吸入流量数据与实验值之间存在一定程度的偏差。最后,本论文根据理论分析结果,设计制作了一种结构可变的气旋流悬浮单元,以此来探究圆柱腔高度、吸入孔直径等设计参数对流量放大效果的影响。实验研究发现,圆柱腔过高不利于悬浮单元从外界吸入空气;吸入孔的直径直接决定了被吸入的空气进入圆柱腔的阻力大小,因此,增大吸入孔的直径能够有效地提高流量放大效果。
[Abstract]:In this paper, a new type of air suspension unit with the function of flow amplification is studied.Cyclone flow suspension unit inhale extra air by negative pressure generated by high speed rotating airflow, which can greatly reduce air consumption, and can bring considerable energy saving effect in the application of glass substrate non-contact suspension transport.At present, the research of cyclone flow suspension unit is still in its initial stage. Therefore, it is very important to understand the structure of flow field and the characteristics of flow amplification and clarify the internal mechanism of flow amplification for the future optimization design and application development.Firstly, we analyze the pressure distribution at the vent gap of the swirl suspension unit in detail through experimental research, and point out the relationship between the pressure distribution curve and the flow field, and the influence of the suction hole on the flow field of the suspension unit.Then, we study the effects of gap height and supply flow on the flow field, pressure field and suction flow of suspension unit.In addition, the flow line, velocity field and pressure distribution in the cylindrical cavity and the slot are discussed by using the fluid numerical simulation (CFDs).The basic principle of the flow amplification by the swirl suspension unit and the influence of the suction hole on each region of the suspension unit are clarified.Based on the above experimental data and the work of numerical simulation of fluid, we simplify the Navier-Stokes equation, combine the conservation of angular momentum and the empirical model near the wall, and put forward the mathematical model of the flow field of the gas-swirl suspension unit.Compared with the experimental results, the mathematical model can well reproduce the velocity distribution, the pressure distribution shape and the tendency of the suction flow curve of the gap, because the air flow in the vertical direction and the resistance of the upper and lower wall are ignored.So there is a certain deviation between the pressure data and the suction flow data and the experimental data.Finally, according to the results of theoretical analysis, a variable structure swirl suspension unit is designed and fabricated to explore the influence of the design parameters such as the height of cylindrical cavity and the diameter of suction hole on the effect of flow amplification.The experimental results show that the cylinder cavity is too high for the suspension unit to inhale air from the outside, and the diameter of the suction hole directly determines the resistance of the inhaled air to the cylindrical cavity.Increasing the diameter of the suction hole can effectively improve the effect of flow amplification.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN873

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