Injection molding Mold filling

Ke Twords computer aided engineering (CAE), computer simulation, fiber orientation prediction, fiber orientation modelling, fiber reinforced thermoplastics, finite difference method, finite element method (FEM), flow, glass fiber reinforcement, injection molding, mold filling analysis, warpage. 

Soil, S.K. and Chang, C. J., 1986. Boundary conditions in the modeling of injection mold-filling of thin cavities. Polym. Eng. Sci. 26, 393-399. 

Radial flow between parallel discs is a very common flow type encountered in polymer processing, particularly during injection mold filling. In this section, we seek the velocity profile, flow rates and pressure for this type of flow using the notation presented in Fig. 5.16. 

Today, the most widely used model simplification in polymer processing simulation is the Hele-Shaw model [5], It applies to flows in "narrow" gaps such as injection mold filling, compression molding, some extrusion dies, extruders, bearings, etc. The major assumptions for the lubrication approximation are that the gap is small, such that h < . L, and that the gaps vary slowly such that... 

Gao, F. Patterson, I.A.N. Kamal, M.R. Selftuning cavity pressure control of injection molding filling. Adv. Polym. Technol. 1994,13, 111-120. 

In addition to these shear flow situations, molten polymers are subjected to extensional flow. This occurs in film blowing, fiber drawing, and some injection mold filling situations where straightening and alignment of polymer chains may increase viscosity (Fig. 9). 

Basic studies of flow mechanisms in molding have been lacking for rubber compounds. Almost all published studies have been for thermoplastics. Most of these investigations involve injection mold filling. 

It has been long realized that there are two regimes of injection mold filling. These involve a slowly expanding front or jetting into a mold. Oda et aL [Ol] have shown that jetting into a mold is the result of the polymer or compound having a low extrudate swell. The often complex occurrence of this swell is associated with the melt temperature and its variations in runners. Isayev and his coworkers [13, 14, 16] have extensively studied pressure... 

Harry DH, Parrott RG (1970) Numerical simulation of injection mold filling. Polym Eng Sd... 

Hieber CA, Shen SF (1980) A finite-element/finite-difference simulation of the injection-molding filling process. J Non-Newtonian Fluid Mech 7 1-32 Hill R (1963) Elastic properties of reinforced solids Some theoretical principles. J Mech Phys Solids 11 357-372... 

K. Oda, J. L. White and E. S. Clark, Jetting phenomena in injection mold filling mold filling. Polymer Engineering Science, 16, 585-592 (1976). 

Hieber, C. A. and Shen, S. R, A finite element/finite difference simulation of the injection mold filling process . Journal of Non-Newtonian Fluid Mechanics, 7(1), 1-31, 1980. 

C-Flow Injection Mold Filling Analysis Hardware. Ithaca, NY Advanced CAE Technology, 1987. 

When an injection mold fills, the incoming high-velocity melt stream is resisted by, and must displace, the air in the feed system and cavities. Molders often rely on incidental air gaps between the parting faces and between the assembled parts of the core and cavity to provide a leakage path for air, but this is no substitute for properly engineered venting which should be... 

Mavridis, H., Hrymak, A.N., and Vlachopoulos, J. (1986) Mathematical modeling of injection mold filling a review. Adv. Polym. Technol, 6, 457-466. 

Kamal, M.R., Chu, E., Lafleur, P.G., and Ryan, M.E. (1986) Computer simulation of injection mold filling for viscoelastic melts with fountain flow. Polym. Eng. Sci., 26, 190-196. 

Kamal, M.R., Goyal, S.K., and Chu, E. (1988) Simulation of injection mold filling of viscoelastic polymer with fountain flow. AIChE J., 34, 94—106. 

Nguyen-Chung T (2004) Flow analysis of the weld line hmnation during injection mold filling of... 

Improperly placed fiber preforms can cause dry spots or pools of resin on surface of finished part. Fiber preforms can also move during injection mold filling without proper fixing arrangements within mold. 

Hieber, C. A. and S. E. Shen. 1980. A Finite Element/Finite Difference Simulation of the Injection Molding Filling Process. J. Non-Newtonian Fluid Mechanics, 7, 1—32. 

Figure 15.23 Jetting in injection-mold filling. (From Ref. 30)...

While, J. L., Fluid Mechanical Analysis of Injection Mold Filling, Polym. Eng. Sci., 15, 44-50, 1975. 

Kamal, M. R., E. Chu, P. G. Lafleur, and M. E. Ryan, Computer Simulation of Injection Mold Filling for Viscoelastic Melts with Fountain Flow, Polym. Eng. Set, 26, 190-196, 1986. 

In this paper, a numerical solver based on Finite Volume Method (FVM) is developed to solve the governing equations. The solver has been successfully applied in injection molding filling simulation [2]. Numerical experiments confirm the reliability and efficiency of the solver. 

In this work, a numerical solver based on Finite Volume Method (FVM) is developed to solve the governing equations. The solver has been successfully applied in injection molding filling simulation [2]. Numerical experiments confirm the reliability and efficiency of the solver. Currently the proposed solver can handle tetra, hexa, prism, pyramid, and mixing elements. Prism layer element can also be used for analysis to improve thermal boundary resolution while without extensive refining of mesh. This is valuable in mold cooling analysis that may involve millions of elements. 

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