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Planetary wheel agitating mill performance analysisMixing equipment is a kind of widely used, a wide range of fluid machinery,suitable for chemical industry, metallurgy, medicine, food and feed etc.Mixing operation is the important unit operations found in process industry, mixing process is in the flow field of momentum, heat and mass transfer and chemical reaction process.With the development of the industry, the shortage of the traditional mixer is more and more obvious, urgent need to study a new type of mixing device.Today, the development of blender to two aspects: one is to improve the original agitator, such as various combined-type agitator;Second is to design a new type of agitator, variable diameter mixer, such as mixer.This blender can increase and decrease the fin to adapt to different height of stirred tank.In addition, the blender miniaturization research has made great progress, such as micro magnetic stirrer.Mechanical stirrer with simple structure, good mixing performance, high efficiency and adapt to the wide range of materials, etc.The author designs a new type of planetary wheel mixer, analyses the structure characteristics and working principle of the application software for simulating the flow field, and through the experiment with anchor, advancing the agitator performance comparison.Planetary wheel agitator structure simple, two auxiliary shaft mixer shaft into a symmetrical distribution, two auxiliary shaft into a symmetric distribution on the blade.Mixer, blender pass mechanical energy to the fluid and the fluid with circumferential velocity;Also made up of two pairs of blade planetary wheel rotation under fluid drive.In round two planets, under the action of fluid through a blade to drain out, fluctuation two parts in a stirred tank formation.Part of the fluid from the top of the stirred tank along the spindle inflow and outflow in the central part of the blade, form a circle;Another part of the fluid from the bottom of the stirred tank in central blade along the spindle inflows and outflows, forming another cycle.So that the flow pattern of the media produce large radial flow and axial flow and minimize the tangential flow, at the same time increased the medium flow rate, uniform medium flow.Each type mixer in different fluid flow during operation, and the fluid flow pattern is determined by the working principle of mixer.Planetary wheel mixer working principle is as follows: the principle of centrifugal force, planetary wheel blender rotates, make the effect of fluid by centrifugal force, thrown by the agitator center to the periphery, at the same time make the fluid produces circumferential flow.Due to the blade shaft end near and far end shaft linear velocity, different blade resistance unbalance, thus pushing on both sides of the blade rotation.Under the action of fluid flow in the blade around the auxiliary shaft rotation, and are constantly into the periphery.Thrown by the planets round was collected between impeller liquid, under the action of kinetic energy, along the radial and circumferential direction, under the action of medium resistance can converted to static pressure.Static pressure causes the liquid to flow between the wheel, so the action of the two impeller not only have the effect of the diversion, also have the function of the pipeline unicom device, is an energy conversion device.Mixing is an important chemical reaction process operation, process involving fluid dynamics, heat transfer, mass transfer and chemical reaction process.Mixer impeller forms there are dozens of different and new form still appear constantly.This paper introduces a new type of planetary mixer, the mixer is different from the existing planet stirrer, only one drive shaft, a driving force of the planet wheel rotation from liquid resistance.Planetary wheel planetary mixer structure, consisting of the main structure by the transmission shaft, planets (including blade and impeller wheel Yi), planetary wheel frame, coupling sleeve, fastening nut and connection parts, such as blade welding on the planet impeller wheel yi, blade and impeller wheel jinyi constitute planet, impeller installed in the free rotation planets wheel rack on the axis of the planet wheel frame and connection sleeves made of an organic whole.Join set by the fastening nut and connection with the shaft connection, connection is used to transfer torque, for key or pin, etc., at the bottom of the fastening nut, used to lock and load, force on the top of the shaft and join.Is mainly used to transfer the power, drive shaft coupling is used to transfer torque, planetary wheel rack of impeller shaft support and installation for planets, connection sleeves made of an organic whole, at the same time.Connection sleeves with the shaft and transmission torque, connection sleeves and the matching of the drive shaft for transition fit, and with the aid of connecting parts and fastening nut will join tight on the drive shaft, planetary wheel pass mechanical energy to a liquid.It through the bearing or the shaft sleeve and planetary wheel rack shaft are connected, the impeller blade and wheel yi constitute an organic whole, from leaf axis relative to the wheel yi can parallel installation.Installation can also be tilted Angle.Planet stirrer symmetric impeller installed 2 4 planets, planet impeller diameter less than five times the diameter of the mixer, and the diameter of planet stirrer vessel diameter ratio of 1:3.Planet impeller symmetric install 3 to 8, leaves can be made into flat blade, also can be made into curved blade.Planetary impeller depends on the container medium heightLiquid level height, installed with the top of the impeller is apart from the liquid surface and bottom toe underside should keep a certain space.Planets impeller wheel frame dragging and fluid resistance, under the joint action of both with the drive shaft revolution, is relatively planet wheel rotation.The planet stirrer planet wheel rotation, the blade will launch, fluid along the radial direction along the radial direction of fluid flow in the wall of the block, to the center to blender at both ends up and down stream of people again, thus forming a high turbulent fully mixed zone, and fluid particle axial flow for high-speed spiral, under the low speed can produce strong radial flow and axial flow, eliminate the dead zone in the container.Dielectric mixing, significantly reduce the reaction time.Blade shape can be flat, also can be a propeller or helical vane, the primary flow pattern of the latter is axial flow and mixing effect is better.Due to the role of the planetary wheel, the flow of the liquid in the container is very complex, the mainstream of the liquid in the container on the macro model of radial flow and axial flow.Through the observation of the tracer particles, the flow of the liquid particle type and inlet velocity distribution is uneven, around the planet wheel, the size of the liquid particle velocity and direction are alternating, therefore, under the action of stirrer, liquid particle was thrown from central blade, then the spiral flow, again from the agitator fluctuation in central area, fluid turbulent intense, even if they dont add baffle, container dead zones will not exist.Rotational speed.Increased, the circumferential velocity will increase, so the spindle speed should be controlled. Driving force of the planet wheel rotation from the liquid resistance.The mainstream of the liquid in the container on the macro model of radial flow and axial flow.When the planet wheel rotation, blade will introduce fluid along the radial direction, due to the wall block, then the spiral flow, respectively from the blender fluctuation in central area, forming a high turbulent fully mixed zone.行星轮式搅拌磨性能分析搅拌混合设备是一种应用广泛、品种繁多的流体机械，适用于化工、冶金、医药、食品和饲料等领域。搅拌操作是过程工业中重要的单元操作，搅拌过程就是在流动场中进行动量、热量、质量传递及化学反应的过程。随着工业的发展，传统搅拌器的不足越来越明显，迫切需要研究新型的搅拌装置。目前，搅拌器向着两个方面发展：一是改进原有的搅拌器，如各种组合式搅拌器；二是设计新型的搅拌器，如可变直径搅拌器、分列式搅拌器。这种搅拌器可以通过增加和减小翅片来适应不同高度的搅拌釜。另外，搅拌器微型化的研究也取得了很大的进展，如微型磁力搅拌器等。机械搅拌器具有结构简单、搅拌性能好、效率高及适应物料范围广等优点。笔者设计了一种新型的行星轮式搅拌器，分析了其结构特征和工作原理，应用软件对其流场进行模拟，并通过实验与锚式、推进式搅拌器进行了性能对比。 行星轮式搅拌器的结构简单，搅拌器的两个副轴相对主轴成对称分布，两对桨叶相对副轴成对称分布。搅拌器工作时，搅拌器将机械能传递给流体并使流体具有圆周速度；同时由两对桨叶组成的行星轮在流体推动下自转。在两个行星轮的作用下，流体通过桨叶向外流出，在搅拌釜内形成上下两部分。一部分流体从搅拌釜顶部沿主轴流入并在桨叶的中部流出，形成一个循环；另一部分流体从搅拌釜底部沿主轴流入并在桨叶中部流出，形成另一个循环。这样的流型使介质产生大的径向流和轴向流，尽量减小切向流，同时加大了介质流量，介质流动均匀。 每种搅拌器在运转时产生不同的流体流型：而流体流型是由搅拌器的工作原理决定的。行星轮式搅拌器的工作原理如下：离心力原理，行星轮式搅拌器旋转时，使流体受离心力的作用，由搅拌器中心抛向外围，同时使流体产生周向流动。由于桨叶近轴端和远轴端的线速度不同，桨叶受阻力不平衡，因而推动两侧的桨叶自转。流体在桨叶的作用下绕副轴旋转，并不断地被抛向外围。行星轮之间汇集了被叶轮抛出的液体，在动能的作用下，沿着径向和周向方向流动，在介质阻力的作用下转化为静压能。静压导致液体向轮间流动，所以两个叶轮的作用不仅起到导流的作用，也具有管道联通器的作用，是一个能量转换装置。搅拌也是化工反应过程的重要操作，搅拌过程涉及流体力学、传热、传质及化学反应等多种过程。搅拌器叶轮形式目前已有几十种，而新的形式还在不断出现。本文介绍的一种新型行星式搅拌器，这种搅拌器不同于已有的行星式搅拌器，传动轴只有一个，行星轮自转的驱动力来自液体阻力。行星轮构成的行星式搅拌器结构，主体结构由传动轴、行星叶轮包括叶片和轮毅)、行星轮架、联接套、紧固螺母和联接件等部件组合而成，叶片焊接在行星叶轮轮毅上，叶片与轮毅共同构成行星叶轮，行星叶轮以自由转动方式安装在行星轮架的转轴上，行星轮架与联接套制成一体。联接套由紧固螺母和联接件与传动轴连接在一起，联接件用于传递扭矩，可以为键或销等，底端的紧固螺母，用于锁紧并承重，传动轴顶端与外动力联接。 传动轴主要用于传递动力，联接件用于传递扭矩，行星轮架上的轴用于支撑和安装行星叶轮，同时与联接套制成一体。联接套与传动轴配合并传递扭矩，联接套与传动轴的配合为过渡配合，并借助联接件和紧固螺母将联接套固紧在传动轴上，行星叶轮将机械能传递给液体。它通过轴承或轴套与行星轮架上的轴相联接，行星叶轮由叶片与轮毅构成一体，叶片相对于轮毅轴线可以平行安装。也可以倾斜一定角度安装。 行星式搅拌器对称安装24个行星叶轮，行星叶轮直径小于搅拌器直径的5倍，行星式搅拌器直径与容器直径之比为1：3。行星叶轮上对称安装3-8个叶片，叶片可以制成平面叶片，也可以制成曲面叶片。行星叶轮高度取决于容器介质的液面高度，安装后叶轮的上端距液平面和下端趾底面都要保持一定空间。 行星叶轮在行星轮架的拖动和流体阻力的共同作用下，既随传动轴公转，还相对行星轮轴自转。在行星式搅拌器行星轮自转时，叶片将流体沿径向方向推出，沿径向方向运动的流体在器壁的阻挡下，转向搅拌器上下两端再流人中心部，从而形成高湍动的充分混和区，且流体质点的轴向流线为高速螺旋线，在低转速下即可产生较强的径向流和轴向流，消除了容器内的“死区”。介质混合均匀，反应时间显著降低。 叶片形状可以是平的，也可以是螺旋桨或斜叶式的，后者产生的主导流型是轴向流，搅拌效果更好。 由于行星轮的作用，液体在容器内的流动非常复杂，宏观上容器内液体的主流型为径向流和轴向流。通过对示踪粒子的观察，液体质点的流动类型和各部的速度分布是不均匀的，在行星轮的周围，液体质点速度的大小和方向都是交变的，因此，在搅拌器的作用下，液体质点从叶片中部被抛出，然后呈螺旋线流动，再从搅拌器的上下进人中心区，液体湍动剧烈，即使不加挡板，容器内也不会有“死区”存在。转速。增加，周向速度会增加，因此主轴转速应加以控制。 行星轮自转的驱动力来自液体阻力。宏观上容器内液体的主流型为径向流和轴向流。在行星轮自转时，叶片将流体沿径向方向推出，由于器壁的阻挡，然后呈螺旋线流动，分别从搅拌器的上下进人 中心区，从而形成高湍动的充分混和区。
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