Visualization of Flow & Void In pultrusion Process of thermoplastic composites

Pultrusion is a continuous method for producing profiles with a constant cross section. Mechanical Properties of pultruded composite is related to process parameters such as pulling velocity, Temperature of die, texture of reinforced fibers, etc.
Visualization of Physical variables such as velocity of melted resin, position of backward melt flow, orientation of reinforced fiber in the die can be useful in estimation of degree of impregnation and estimation of quality of pultruded composite. visualization and optimization of these parameters can be a major step to achieve pultruded composite with requested specifications and better performance.
In this research, pultrusion die with glass walls has been used for direct observation of process during pultrusion. glass die has been heated using IR radiation.
In this way important parameters such as, position of molten backflow, velocity profile of melted resin, orientation of reinforced fibers and void state have been observed directly and volume of voids among the die has been reducted about 0.17 instead of first volume and Impregnation Ratio in Y Direction calculated 0.05 * 10-5 m2 and Vx=0.43cm/s ,Vy=0.05cm/s.