胶乳分离机高速转鼓内流场的数值分析

为了得到胶乳分离机高速转鼓在离心力场作用下的内部流场规律,建立胶乳物理特征、转鼓结构及转速与流场压力、速度之间的相互关系。基于FLUENT软件,对仿真建模、边界条件设置、计算方法进行了研究;选择混合多相流和层流模型,利用转鼓流场二维模型对内部流场进行了数值模拟,分析得到了流场的压力云图、速度云图以及出流区速度矢量图,定量评价了不同转速下流场压力、速度的变化,提出了一种利用特征参数验证模型的方法。分析结果表明:转鼓内流体压力、速度与流体所处半径成正比,流体速度、压力分别与转鼓转速呈一次、二次正比例关系,在工作转速下最大液体压力为10.4 MPa,重相出流区比轻相出流区存在更明显的漩涡现象,碟片间隙内液体流动状态为层流,仿真结果与理论计算值、文献压力数据及特征参数实测值较一致,验证了分析模型和分析方法的有效性。本研究为胶乳离心分离工艺、转鼓流场及结构优化提供了理论依据和分析方法。

Numerical Analysis on Flow-field Characteristics of High-Speed Bowl of Latex Disc-separator

In order to obtain distribution of flow field in centrifugal field in high-speed bowl of latex disc-separator,and to establish the relations among pressure-field,velocity-field and latex physical characteristics,blow structural,rotate speed. The model building、boundary restriction conditions and numerical computation method have been examined and debugged based on the FLUENT. The flowfield in the rotating bowl was numerically simulated by the two-dimensional flow field model abiding by principle of hybrid multiple phase flow and laminar flow model. The nephograms of pressure and velocity,the diagram of velocity vector were obtained. The pressure field and the velocity field were quantitatively analyzed under different velocities. The modeling vertification method based on characteristic parameter was proposed. The results indicate that the flow-pressure and the flow-velocity are proportional to the bowl rotation speed and the radius of liquid. Flow pressure is directly proportional to the rotation speed into a quadratic liner relationship,the flow velocity is directly proportional to the rotation speed into a liner relationship. The maximum liquid pressure increases up to 10. 4 MPa in the working speed. The vortex phenomenon of the outlet of heavy phase is more obviously than that of the outlet of light phase. The flow between two discs is primarily laminar. The simulation results are accordant with with the data taken from the theoretical calculation,the document and the experiments. The results show the validity of the model and analysis methods. The methods and results can provide more guidance and reference for analysis of latex centrifugal process and flow filed,structure optimize of latex disc-separator.