Inversion Of Thermal Contact Resistance In Injection Molding

In the injection-molding field, it has been a very important method to control the final quality of the parts by the filling processing parameters. Cooling is playing a very important role in polymer injection processing, and affects molded product quality, cost and cycle time. Meanwhile temperature is one of the most important parameters in injection molding process. Temperature parameter will not only influence cycle time but also result in quality problems. In the past, people believed that mold and polymer has been complete contact. But it is not actual situation. Incomplete contact between mold and polymer is ignored will lead to a certain degree of the error. How to get the thermal conduction resistance is worth of further study. It is difficult for us to get the thermal contact resistance directly. In this paper, an inversion model and solve it by regularization method has been developed. The feasibility of this method is justified with numerical computations.Main contents of this dissertation are as follows:In chapter 1, the background of this dissertation is introduced. The history and current status of CAE technology and introduced and some existing methods for solving inverse problems are surveyed.In chapter 2, the development of the heat transfer is simply presentation. Simulation is mainly utilized in injection molding. Temperature governing equations for cooling process are obtain based on reasonable assumption and simplification. Finite element method is employed to solve these equations.In chapter 3, the influence of thermal conduction resistance on the final quality and dimensions is analyzed and the problem is shown. Corresponding inversion model of flow rates is given.In chapter 4, the Bregman regularization is introduced to modify the model. D-functions are employed as the regularization functions and a homotopy method is employed to widen the convergence region of the method. The algorithmic implementation of Bregman regularization method and some numerical examples are given.In chapter 5, a summary of this thesis and some possible future work with reference to this paper is given.This thesis is supported by the National Natural Science Foundation of China under Grant 10590354,10572031.