کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
670501 1459022 2015 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A non-Newtonian fluid model with an objective vorticity
ترجمه فارسی عنوان
یک مدل مایع غیر نیوتنی با یک وفاداری هدف
کلمات کلیدی
غرور، جریان انعطاف پذیر، مایعات رینر ریولین، ویسکوزیته فرعی ویسکوزیته برشی، ضریب استرس طبیعی
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
چکیده انگلیسی


• We provide a non-Newtonian fluid model with an objective vorticity tensor.
• Two different time scales are used for strain relaxation and rotation recovery.
• The objective vorticity tensor introduces a strain softening effect.
• The model simultaneously predicts shear thinning and extensional thickening.

Closed-form constitutive equations that explicitly correlate kinematic variables such as the strain rate tensor to the stress tensor are highly desired in modeling of polymeric flow of practical relevance. However, conventional fluid models of the Reiner–Rivlin type encounter a difficulty in differentiating flow types and predicting realistic elastic effects. In this paper, a constitutive model of type τ=τ(L‾) where L‾ is an objective velocity gradient is presented to treat the objective rotation of a fluid-like material containing a conformational structure. Specifically, this model contains two different relaxation processes to separately tackle rotation and straining. The base model with three parameters is able to simultaneously model shear thinning and extensional thickening as well as normal stress differences in simple shear. Additional model accuracy is achieved by incorporating finite stretch and disentanglement effects.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Non-Newtonian Fluid Mechanics - Volume 218, April 2015, Pages 99–105
نویسندگان
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