Extrusion Die Design – Beyond Preliminary Extrusion Simulation
M. Kostic
www.kostic.niu.edu/extrusion
As we all know, polymer extrusion is a very complex 3-D process of a very complex material (properties vary with process shearing itself in addition to temperature, and not only viscosity). Therefore, proper die design is much more than our preliminary simulations, and even more than very careful 3-D simulation. “The Devil is in details” and small deviations will make critical difference for proper die design. We must fully understand basic fundamentals and software features, to be able to get output-results’ sensitivity on critical input parameters. That will provide relative precision accuracy of the simulation, for efficient “tuning” of the final die-design. The absolute accuracy must be obtained by “calibrating” simulation parameters with real output-dimensions of the extrudate from the extruder itself. Only then, effective die-design procedure could be developed. As I said before, simulation and experimentation are not replacing each-other, but may complement each-other synergistically (result will be greater than the sum of its parts). Therefore, it is important, actually critical that we be involved in learning and fully understanding actual extrusion run and its measurement and control functions in Fermilab, in order to be able to finalize precision die-design. It happened that I have working experience and expertise in instrumentation and measurements, including computerized data acquisition and control. I have worked in the area of non-Newtonian flow, including measurements of rhological properties, and heat transfer, the latter being very critical for controlling the consistency of polymer properties and extrusion processes, see related publications below. I am also equally interested in numerical simulation with commercial software and experimental research. Working knowledge of ME faculty is very important since we can not rely on MS students: often we spend more time on their training than what we get from them, and unfortunately we do not have PhD students.
►Presentation 1 [PPT] (mod) ►Presentation 2 [PPT] at 2004 North American CFD Summit: Fluent Users' Group Meeting,
Related M. Kostic’s Publications
1. Kostic, M. and L. G. Reifschneider, "Extrusion Die Design*" Encyclopedia of Chemical Processing (S. Lee, Editor); (c) 2005 by Dekker, ISBN: 0-8247-5563-4 (Hardcover 5 Volume Set, 3640 pages); (c) 2006 by Taylor & Francis, ISBN: 0-8247-5499-9 (electronic, Abstract).
2. Vaddiraju, S.R., M. Kostic, L. Reifschneider, A. Pla-Dalmau, V. Rykalin, and A. Bross, “Extrusion Simulation and Experimental Validation to Optimize Precision Die Design,” ANTEC 2004, The Annual Technical Conference, Society of Plastics Engineers, Chicago, May 16-20, 2004.[PPT]
3. Reifschneider, L.G., M. Kostic, and S.R. Vaddiraju, “Computational Design of a U-Profile Die and Calibrator,” ANTEC 2004, The Annual Technical Conference, Society of Plastics Engineers,
4. Kostic, M. and H. Tong, "Investigation of Thermal Conductivity of a Polymer Solution as Function of Shearing Rate," The 1999 International Mechanical Engineering Congress and Exposition (IMECE),
5. LeBlanc, G., Secco, R.A., and Kostic, M. "Viscosity" a chapter in "The Measurement, Instrumentation and Sensors Handbook" (J.G. Webster, Editor-in-Chief), ISBN: 0-8493-8347-1, CRC Press, 1999.
6. Kostic, M., "Data Acquisition And Control for An Innovative Thermal Conductivity Apparatus Using LabVIEWâ Virtual Instrument." Laboratory Robotics and Automation Journal, Vol.10, No.2, pp.107-111, Wiley, 1998.
7. Kostic, M., "Data Acquisition And Control Using LabVIEWâ Virtual Instrument For An Innovative Thermal Conductivity Apparatus." NIWeek 97 Annual Conference, National Instruments,
8. M. Kostic, "Different Non-Newtonian Reynolds and Prandtl Numbers, Their Usage and Relationships," The 1994 ASME International Mechanical Engineering Congress and Exposition,
9. M. Kostic, "On Turbulent Drag and Heat Transfer Reduction Phenomena and Laminar Heat Transfer Enhancement in Non-Circular Duct Flow of Certain Non-Newtonian Fluids," Int. J. Heat & Mass Transfer, Vol.37, Suppl.1, p.133-147 (1994).
10. M. Kostic, "The ultimate asymptotes and possible causes of friction drag and heat transfer reduction phenomena," Journal of Energy Heat and Mass Transfer, Vol.16, No.1, p.1-14, (1994).
11. J. Jimenez and M. Kostic, "A Novel Computerized Viscometer/Rheometer," Review of Scientific Instruments Journal, Vol.65(1), p.229-241, American Institute of Physics (1994).
12. M. Kostic, "Influence of viscosity function simplification on non-Newtonian velocity and shear rate profiles in rectangular ducts." Int. Comm. Heat Mass Transfer, Vol.20, p.515-525 (1993).
13. J.P. Hartnett and M. Kostic, "Turbulent friction factor correlations for power law fluids in circular and non-circular channels." Int. Comm. Heat Mass Transfer, Vol. 17, p. 59-65 (1990).
14. J.P. Hartnett and M. Kostic, Heat Transfer to Newtonian and Non-Newtonian Fluids in Rectangular Ducts. Advances in Heat Transfer, Vol. 19, p.247-356, Academic Press, 1989.
NOTE: This is a 110 page article in the prestigious Academic Press' hard-cover series (periodicals), where the latest state-of-the-art of research and knowledge in different fields are presented.
15. M. Kostic and J.P. Hartnett, "Heat transfer to water flowing turbulently through a rectangular duct with asymmetric heating." Int. J. Heat Mass Transfer, Vol. 29, p. 1283-1291 (1986).
16. M. Kostic and J.P. Hartnett, "The effects of fluid elasticity on laminar flow in rectangular duct." ZAMM, (Z. Angew. Math. Mech.), Vol. 66, p. T239- T241,
17. J.P. Hartnett and M. Kostic, "Heat transfer to a viscoelastic fluid in laminar flow through a rectangular channel." Int. J. Heat Mass Transfer, Vol. 28, p. 1147-1155 (1985).
18. M. Kostic and J.P. Hartnett, "Heat transfer performance of aqueous polyacrylamide solutions in turbulent flow through a rectangular channel." Int. Comm. Heat Mass Transfer, Vol. 12, 483-490 (1985).
19. M. Kostic and J.P. Hartnett, "Predicting turbulent friction factors of Non-Newtonian fluids in non-circular ducts." Int. Comm. Heat Mass Transfer, Vol. 11, p. 345-352 (1984).
