Design sensitivity analysis and optimization for polymer sheet extrusion and mold filling processes

Abstract

SUMMARYA polymer processing design methodology is presented which can be used to improve the production of plastic components manufactured via extrusion and injection molding processes. The design method combines polymer process modelling, design sensitivity analysis and numerical optimization. It is applicable to systems with creeping ow of purely viscous non-Newtonian uids through thin cavities where the lubrication approximation may be applied. An analysis and an adjoint design sensitivity analysis are presented for the steady-state coupled system which describes the pressure and residence time distributions in sheeting dies. The resulting methodology is then used to deÿne the optimal die cavity shape and relevant process parameters in a sheeting die design example. A second example considers tooling and process design for the polymer injection molding process. A coupled transient mold ÿlling analysis and design sensitivity analysis based on the direct di erentiation method are developed where attention is given to describing the location of the gates in the mold cavity. The latter is illustrated through the process design of a plastic automotive component.

Analysis of the fluid–structure interaction in the optimization‐based design of polymer sheeting dies

“…6,23,30 The specific die geometry used in this study is shown in Figure 3; it is symmetric about the die's centerline (i.e., x ¼ 0) and is similar to that presented elsewhere by Gifford. 13 It consists of four major regions, as shown in Figure 3: the manifold, preland, secondary manifold, and land.…”

“…The Hele-Shaw model is widely employed in injection and compression molding 22 and has also been applied to sheet extrusion dies. 6,7,8,[23][24][25][26] On the basis of these assumptions, the mass and momentum conservation equations reduce to a single differential equation:…”

Determination of Optimal Manufacturing Parameters for Injection Mold by Inverse Model Basing on MANFIS

“…It is convenient to diagnose and modify designed before product manufacture for reducing cost and time, and lev-eling up quality. However, even though those modern computer-aided technologies as mentioned above play an important role in manufacture, the subject of how to determine optimal manufacturing parameters for extremely matching product required still exists [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24]. Although there are a lot of methods such as statistical regression calculation, neural network model and genetic algorithm, grey relational analysis, and fuzzy theory etc.…”

Optimization-based design of polymer sheeting dies using generalized Newtonian fluid models

“…Two-dimensional (often referred to as 2.5 D) simulations provide a computationally efficient alternative to three-dimensional methods, while avoiding many of the simplifying assumptions and geometric restrictions of existing one-dimensional design equations (see, e.g., Refs. [15][16][17][18][19][20]. Sartor [15] was perhaps the first to combine numerical optimization with a two-dimensional flow network analysis to iteratively solve the die design problem using a powerlaw fluid model.…”

“…16 and 17, which greatly reduced the computational effort required in the design calculations. This approach was extended to dies having a uniform exit velocity and residence time; examples include coat-hanger dies [17] and dies with a general die cavity height distribution [19]. More recently, this die design approach was extended to address variability during operation [23].…”