A thin filament model is used to analyze the stability of a viscoelastic thread subject to uniaxial stretching. Linear stability analysis is carried out for a number of different constitutive models, namely the Johnson–Segalman, Giesekus, Phan–Thien Tanner, and FENE–CR. Our analysis shows that stability is controlled by the competing effects of surface tension which is destabilizing and axial n...

In this paper, we propose a new entropy satisfying finite volume method to solve the FokkerPlanck equation of FENE dumbbell model for polymers, subject to homogeneous fluids. Both semi-discrete and fully discrete schemes satisfy all three desired properties: i) mass conservation, ii) positivity preserving, and iii) entropy satisfying. These ensure that the computed solution is a probability den...

In the String & Binders Switch (SBS) model 1,2 a chromatin filament is represented as a self-avoiding (SAW) polymer chain, composed by N beads. Each bead of the chain interacts with diffusing Brownian particles (binders) having a molar concentration c. The scale of their binding energy to a cognate polymer bead is named í µí°¸!"#. The beads of the chain and the binders are subject to Brownian m...

هیدروفرمینگ لوله به‌طور گسترده، در تولید قطعات ساختاری اتومبیل استفاده می‌شود. یکی از خصوصیات تولید‌شده با این فرایند، نسبت استحکام به وزن بالا می‌باشد. لولۀ فشار پایین، روش‌های پیشنهاد‌شده برای حل مشکلات قبیل نیاز بالای سیال و آب‌بندی روش انجام پایین لوله، شبیه فشردن جسم جامد است آن برخلاف بالا، قالب بالایی طول فرایند ثابت نبوده هم‌زمان اعمال داخلی حرکت کرده را تحت قرار می‌دهد. مقاله، لوله‌های...

Fluid dynamic simulations using the FENE-P model of polymer physics are compared to those an incompressible Newtonian fluid base case in order understand role elasticity formation vortices a 90° bend narrow channel. The analysis bridges flow behavior purely elastic and that fluid. We evaluated how four dimensionless numbers—Reynolds number (Re), Weissenberg (Wi), viscosity ratio (?), (El)—affec...

Viscoelastic flow in a square cavity is studied in detail for the FENE-CR model with a given value of extensibility. A finite volume method was employed to predict both the steady flows resulting from movement of the top cavity wall and also the recoil flows that follow the cessation of that lid-wall motion, when the fluid possesses viscoelastic properties. It is shown that this recoil flow can...

Novel kinetic models for both Dumbbell-like and rigid-rod like polymers are derived, based on the probability distribution function f(t, x, n, ṅ) for a polymer molecule positioned at x to be oriented along direction n while embedded in a ṅ environment created by inertial effects. It is shown that the probability distribution function of the extended model, when converging, will lead to well acc...