The Calculate Of Fiber Orientation In Center-gated Disk Injection Produce

As the wildly used of fiber reinforced plastics (FRP), it is more and more urgent to study its property. Unlike the ordinary reinforced material, the fiber is long in length, so the fiber tends to show orientation in the flow field. And anisotropy may appear in the fiber reinforced plastics. So most of the research of the fiber reinforced plastics focus on the orientation of the fiber. In the research, the research object is sediment fluid of fiber, the situation of the fiber orientation in the fluid can be described with two Euler angles. When set up the relationship between the Euler angles and the time, the orientation situation of the fiber can be got.In 1922, Jeffery obtained the motion function of the single fiber which is suspends in the uncompressible Newtonian fluid. This thesis puts the Jeffery function in the Three-dimensional flow field. For eliminating some singularity in mathematical expression, import the notion of Co-rotational coordinate system. Obtain a more pithily expression of Jeffery function. Based on this, set up a Center-gated disk model, by researching on the model, get some conclusion below:(1) The fibers in the fluid will rotate in two ways, one is rotate in cycle periodic, the other is progress step by step to the very position.(2) In the surface layer of the model, there is only shear action, the fibers will orients parallel the shear direction. The fibers will rotate periodic in the flow field, but the fibers rotate slower in the shear direction and rotate faster in other direction. So, most of the fibers will orients parallel the shear direction.(3) In the central layer of the model, there is only stretcher action. The orientation of the fibers is parallel the stretcher direction. When the fiber arrive the oriental situation, it will keep its situation and won't move anymore.(4) In the layer between the surface layer and the central layer, there is both shear action and stretcher action, so there is two situation of the fiber, one is parallel the shear direction, the other is parallel the stretcher direction. As the change of the height, the shear action and the stretcher will change their statues. When the shear action is on the dominance, most of the fiber will parallel the shear direction, on the other way, most of the fiber will parallel the stretcher direction.(5) There is other factors that affect the orientation of the fiber such as initial angle of fiber, injection speed, and the ratio of length to diameter of the fiber. The initial angle of fiber will affect the orientation speed of stretcher fluid and the rotate speed of shear fluid. As the increasing of injection speed, the rotate speed of the fiber will increase. the ratio of length in the shear fluid will change the period of the fiber. The long the fiber is, the more time will be taken in the period.