Numerical and Experimental Validation of Natural Fiber Orientation in Viscous Fluid of Injection Cavity

In an injection moulded product, the orientation of short fiber in polymer composite influences the strength of the product. A method was developed to predict orientation of natural fiber in thermoset composite. The purpose of this investigation is to predict the orientation of natural fiber in a viscous fluid and to study fiber flow in mould cavity. An experimental set up was developed on injecting viscous fluid with short natural inside the transparent mould cavity and visualize the orientation of short natural fiber and flow front during filling period of cavity. The proposed model for natural fiber orientation was derived by coupling the tangential orientation of natural fiber in flow front and constant curling factor in angular velocity of fluid element. The orientation angle was predicted through proposed model at specified position and was validated with experimental method through digitized image analysis technique.