Fluid flow in coat-hanger die of melt blowing process: comparison of numerical simulations and experimental measurements

Abstract

The coat-hanger die is an important part in the melt blowing process, the performance of which is characterized by the flow uniformity at its outlet. The primary objective of this study is to validate the finite element method applied in the simulation of fluid flow in the coat-hanger die, so as to search for the optimal flow channel geometry based on simulation and optimization algorithms. The fluid flow in the coat-hanger die is simulated through three-dimensional finite element method in this paper. Simulation results are experimentally verified qualitatively and quantitatively using particle image velocimetry. Good agreements are obtained in the flow patterns and velocities calculated at the die outlet, which suggests that the numerical methodology can reliably predict the details of fluid flow in the coat-hanger die.

Keywords

Finite element method coat-hanger die melt blowing process particle image velocimetry validation

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References

Matsubara Y. Geometry design of a coat-hanger die with uniform flow rate and residence time across the die width. Polym Eng Sci 1979; 19(3): 169-172.

Matsubara Y. Design of coat-hanger sheeting dies based on ratio of residence time in manifold and slot. Polym Eng Sci 1980; 20(11): 716-719.

Matsubara Y. Residence time distribution of polymer melts in the linearly tapered coat-hanger die. Polym Eng Sci 1983; 23(1): 17-19.

Liu TJ , Liu LD and Tsou JD A unified lubrication approach for the design of a coat-hanger die . Polym Eng Sci 1994; 34(7): 541-549.

Wang Y. The flow distribution of molten polymers in slit dies and coat-hanger dies through three-dimensional finite element analysis. Polym Eng Sci 1991; 31(3): 204-211.

Wen SH and Liu JD Three-dimensional finite element analysis of polymeric fluid flow in an extrusion die Part I: Entrance effect. Polym Eng Sci 1994; 34(10): 827-834.

Yu YW and Liu TJ A hybrid 3D/2D finite element technique for polymer processing operations . Polym Eng Sci 1999; 39(1): 44-54.

Huang YH , Gentle CR and Hull JB A comprehensive 3-D analysis of polymer melt flow in slit extrusion dies. Adv Polym Tech 2004; 23(2): 111-124.

Meng K. , Wang XH and Huang XB Analysis of the stagnation phenomenon in the coat-hanger die of melt blowing process. J Appl Polym Sci 2008; 108(4): 2523-2527.

10.

Sienz J. , Bates SJ and Pittman JFT. Flow restrictor design for extrusion slit dies for a range of materials: simulation and comparison of optimization techniques. Finite Elem Anal Des 2006; 42: 430-453.

11.

Meng K. , Wang XH and Huang XB Optimal design of the coat-hanger die used for producing melt-blown fabrics by finite element method and evolution strategies. Polym Eng Sci 2009; 49(2): 354-358.

12.

Lebaal N. , Schmidt F. and Puissant S. Design and optimization of three dimensional extrusion dies, using constraint optimization algorithm. Finite Elem Anal Des 2009; 45: 333-340.

13.

Pittman JFT and Sander R. Thermal effects in extrusion: slit dies. Int Polym Proc 1994; 4: 326-345.

14.

Sun Q. and Zhang D. Analysis and simulation of non-newtonian flow in the coat-hanger die of a meltblwon process. J Appl Polym Sci 1998 ; 67(2): 193-200.

15.

Ford MD , Nikolov HN , Milner JS , Lownie SP , DeMont EM , Kalata W. , et al. PIV-measured versus CFDpredicted flow dynamics in anatomically realistic cerebral aneurysm models. J Biomech Eng 2008; 130(2): 21015-21023.

16.

Othman S. , Wahab AA and Raghavan VR Validation by PIV of the numerical study of flow in the plenum chamber of a swirling fluidized bed. CFD Lett 2010 ; 2(2): 85-96.

17.

Non SY and Kim DH Three-dimensional modeling of non-Newtonian fluid flow in a coat-hanger die . Korean J of Chem Eng 1995; 12(2): 236-243.

18.

Chen C. , Jen P. and Lai FS Optimization of the coat-hanger manifold via computer simulation and an orthogonal array method. Polym Eng Sci 1997; 37(1): 188-196.