Visualization of the surface tension and gravitational effects on flow injection in center-gated disks

Flow injection in center-gated disks is numerically studied in this paper for possible applications in the manufacturing of composite materials in microgravity environment. The numerical method, which combines the finite element method with a predictor/corrector scheme, is used to determine the transient flow field. The effects of gravitation and surface tension on the development of flow front profile and velocity field are examined for a wide range of the governing parameters (namely, the capillary and Bonds numbers). It has been found that surface tension tends to hold the flow front in symmetric shape while gravitation is to distort it. The balance of these two forces has significant effects on the front shape, front tip traveling speed and required injection pressure. Good agreement is found between the numerical prediction and the experimental results concerning the advancement of the flow front and the front shape. The present results provide useful information in the design of resin transfer molding process in space.