Two-dimensional simulations of the effect of the reservoir region on the pressure oscillations observed in the stick-slip instability regime

• Autorzy: Taliadorou E. , Georgiou G. , Alexandrou A.
• Języki publikacji: EN

Abstrakty

EN

The time-dependent, two-dimensional compressible Newtonian flow over the reservoir-die region is solved assuming that slip occurs along the die wall following a nonmonotonic slip law. The combination of compressibility and nonlinear slip leads to self-sustained oscillations of the pressure drop and of the mass flow rate at constant piston speed, when the latter falls into the unstable negative slope regime of the flow curve. The effect of the reservoir volume on the amplitude, the frequency and the waveform of the pressure oscillations is studied and comparisons are made with experimental observations concerning the stick-slip polymer extrusion instability.

Słowa kluczowe

EN

stick-slip instability; extrusion; compressibility; slip; pressure oscillations

PL

reologia; polimery

• Wydawca: Oficyna Wydawnicza Uniwersytetu Zielonogórskiego
• Czasopismo: International Journal of Applied Mechanics and Engineering
• Rocznik: 2006
• Tom: Vol. 11, no 2
• Strony: 245--254
• Opis fizyczny: Bibliogr. 17 poz., wykr.

Twórcy

autor

Taliadorou E.

autor

Georgiou G.

autor

Alexandrou A.

• Department of Mathematics and Statistics University of Cyprus, P.O.BOX 20537, 1678 Nicosia, CYPRUS,

Bibliografia

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