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A New Algorithm for non-newtonian flow and Its Application in Mould Filling Process

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Journal of Shanghai Jiaotong university(Science) 2011年第1期16卷 1-10页

作者：韩先洪孔啸周雄辉李锡夔 National Die and Mould CAD Engineering Research Center Shanghai Jiaotong University State Key Laboratory of Structural Analysis of Industrial Equipment Dalian University of Technology

The simulation of injection molding process requires a stable algorithm to model the molten polymer with non-isothermal non-newtonian *** this paper,a staggered and iterative scheme is particularly designed to solve the velocity-pressure-temperature *** consideration of the polymer characteristic of high viscosity and low thermal conductivity,the non-newtonian momentum-mass conservation equations are solved by the Crank-Nicolson method based split (CNBS) scheme,and the energy conservation equation with convective character is discretized by the characteristic Galerkin (CG) *** addition,an arbitrary Lagrangian Eulerian (ALE) free surface tracking and mesh generation method is introduced to catch the front of the fluid *** efficiency of the proposed scheme is demonstrated by numerical experiments including a lid-driven cavity flow problem and an injection molding problem.

关键词： non-newtonian flow injection molding finite element method fractional step algorithm

Large Time Behavior of a Weak Solution for non-newtonian flow

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Northeastern Mathematical Journal 2006年第3期22卷 306-322页

作者：吴珞刘辉昭王宗尧 Department of Mathematics East China University of Science and Technology Department of Mathematics Hebei University of Technology

This paper concerns large time behavior of a regular weak solution for non-newtonian flow equations. It is shown that the decay of the solution is of exponential type when the force term is equal to zero and the domain is bounded. Moreover, the ratio of the enstrophy over the energy has a limit as time tends to infinity, which is an eigenvaiue of the Stokes operator.

关键词： large time behavior non-newtonian flow weak solution

flow and natural convection heat transfer characteristics of non-newtonian nanofluid flow bounded by two infinite vertical flat plates in presence of magnetic field and thermal radiation using Galerkin method

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Journal of Central South University 2019年第5期26卷 1294-1305页

作者： Peyman MAGHSOUDI Gholamreza SHAHRIARI Hamed RASAM Sadegh SADEGHI School of Engineering University of TehranTehran ***Iran School of Engineering Iran University of Science and TechnologyTehran ***Iran

The main goal of this paper is to investigate natural convective heat transfer and flow characteristics of non-newtonian nanofluid streaming between two infinite vertical flat plates in the presence of magnetic field and thermal ***,a similarity transformation is used to convert momentum and energy conservation equations in partial differential forms into non-linear ordinary differential equations (ODE) applying meaningful boundary *** order to obtain the non-linear ODEs analytically,Galerkin method (GM) is ***,the ODEs are also solved by a reliable numerical *** order to test the accuracy,precision and reliability of the analytical method,results of the analytical analysis are compared with the numerical *** respect to the comparisons,fairly good compatibilities with insignificant errors are ***,the impacts of effective parameters including magnetic and radiation parameters and nanofluid volume fraction on the velocity,skin friction coefficient and Nusselt number distributions are comprehensively *** on the results,it is revealed that with increasing the role of magnetic force,velocity profile,skin friction coefficient and thermal performance *** parameter has insignificant influence on velocity profile while it obviously has augmentative and decreasing effects on skin friction and Nusselt number,respectively.

关键词： non-newtonian flow nanofluid flow Galerkin method magnetic field radiation

Reverse Roll Coating flow with non-newtonian Fluids

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Communications in Computational Physics 2009年第8期6卷 536-552页

作者： Jiin-Yuh Jang Peng-Yuan Chen Department of Mechanical Engineering National Cheng-Kung UniversityTainan70101 Taiwan

In this study an incompressible flow with non-newtonian fluids in the reverse roll coating process was ***-newtonian behavior of the coating fluid was accounted by using power law model with power index,n,ranging from 0.8 to *** of roll speed ratio(V2/V1)of the panel roll to the applicator roll and gap distance on the coating film thickness were also *** results were in good agreement with those of experimental data within 15%-20%.Results indicated that the film thickness ratios are function of power-law index,roll speed ration and ratio of roll radius to gap *** equations for film thickness ratio were obtained from numerical results as shown below:■,where t1,t2 and t3 are inlet film,transferred film and leakage film thickness,respectively,n is power-law index,V1 and V2 are roll speed of applicator roll and panel roll,Rm is average radius of two rolls and H0 is gap *** correlations are accurate within 10%for 0.8≤n≤1.2,0.5≤V_(2)/V_(1)≤2,and 7.7×10^(−5)≤H_(0)/R_(m)≤1.54×10^(−4).

关键词： Reverse roll coating non-newtonian flow power-law

GLOBAL SOLUTIONS FOR SOME OLDROYD MODELS OF non-newtonian flowS

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Chinese Annals of Mathematics,Series B 2000年第2期21卷 131-146页

作者： P. L. LIONS (CEREMADE-UMR C.N.R.S. 7534, Universite Paris 9-Dauphine, Place du Marechal de Lattre de Tassigny, 75775 Paris Cedex 16, France.) N. MASMOUDI (CEREMADE-UMR C.N.R.S. 7534, Universite Paris 9-Dauphine, Place du Marechal de Lattre de Tassign CEREMADE - UMR C.N.R.S. 7534 Université Paris 9 - Dauphine Place du Maréchal de Lattre de Tassigny 75775 Paris Cedex 16 France

The authors consider here some Oldroyd models of non-newtonian flows consisting of a strong coupling between incompressible Navier-Stokes equations and some transport equations. It is proved that there exist global weak solutions for general initial conditions. The existence proof relies upon showing the propagation in time of the compactness of solutions.

关键词： Global solution Oldroyd model non-newtonian flow

non-newtonian steady shear flow characteristics of waxy crude oil

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Non-Newtonian steady shear flow characteristics of waxy crud...

Simulation of non-isothermal Injection Molding for a non-newtonian Fluid by Level Set Method

The 9th National Conference on Rheology

作者：黄树新陈鑫鲁传敬侯磊范毓润 Department of Engineering Mechanics Shanghai Jiaotong University Department of Petroleum Storage and Transportation China University of Petroleum State Key Laboratory of Fluid Power Transmission and Control Zhejiang University

The experimental research on the non-newtonian flow characteristic of a waxy crude oil was conducted through a rotational parallel-plates rbeometer *** test temperature is about 6.5℃ higher than its gel *** shear stress and viscosity of the waxy crude oil show sophisticate non-newtonian characteristics in the shear rate of 10-10 s,in which the shear stress can be divided into three parts qualitatively,***-up region,leveling-off region,and stress-up *** indicates that there is a yielding process in shearing for the waxy crude oil at the experimental temperature,which is similar to the yield phenomenon in thixotropy-loop test discussed by CHANG and ***,the steady shear experiment alter the pre- shear process shows that the stress leveling-off region at low shear rate disappears for the waxy crude oil and the stress curve becomes a monotonic climbing one,which demonstrates that the internal structure property presenting through yielding stress at low shear rate can be changed by *** experimental results also show that the internal structure of waxy crude oil presenting at low shear rate has no influence on the shear viscosity obtained at the shear rate higher than *** generalized newtonian model is adopted to describe the shear-thinning viscosity property of the waxy crude oil at high shear rate.

关键词： waxy crude oil shear flow non-newtonian flow generalized newtonian model

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cnki会议

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Chinese Journal of Chemical Engineering 2010年第4期18卷 600-608页

作者：杨斌鑫欧阳洁刘春太李强 School of Science Northwestern Polytechnical University Xi' an 710129 Shaanxi China National Engineering Research Center for Advanced Polymer Processing Technology Zhengzhou University Zhengzhou 450002 China

A non-isothermal injection molding process for a non-newtonian viscous pseudoplastic fluid is simulated.A conservative interface capturing technique and the flow field solving method are coupled to perform a dynamic *** validity of the numerical method is verified by a benchmark *** melt interface evolution versus time is captured and the physical quantities such as temperature,velocity and pressure at each time step are obtained with corresponding analysis.A"frozen skin"layer with the thickness increasing versus time during the injection process is *** fact that the"frozen skin"layer can be reduced by increasing the injection velocity is numerically *** fountain flow phenomenon near the melt interface is also ***,comparisons with the non-isothermal newtonian case show that the curvatures of the interface arcs and the pressure contours near the horizontal mid-line of the cavity for the non-newtonian pseudoplastic case is larger than that for the newtonian *** velocity profiles are different at different positions for the non-newtonian pseudoplastic case,while in the case of newtonian flow the velocity profiles are parabolic and almost the same at different positions.

关键词： injection molding Level Set Method two-phase flow non-isothermal non-newtonian flow

A Study on Viscoelastic Fluid flow in a Square-Section 90-Degrees Bend

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Journal of Thermal Science 2003年第4期12卷 337-343页

作者： Mizue Munekata Kazuyoshi Matsuzaki Hideki Ohba Dept. of Mechanical Engineering and Materials Science Kumamoto University Kurokami 2-39-1 Kumamoto JapanDept. of Mechanical Engineering and Materials Science Kumamoto University Kurokami 2-39-1 Kumamoto JapanDept. of Mechanical Engineering and Materials Science Kumamoto University Kurokami 2-39-1 Kumamoto Japan

It is well known that the drag-reducing effect is obtained in a surfactant solution flow in a straight pipe. We investigate about a viscoelastic fluid flow such as a surfactant solution flow in a square-section 90° bend. In the experimental study, drag-reducing effect and velocity field in a surfactant solution flow are investigated by measurements of wall pressure loss and LDV measurements. For the numerical method, LES with FENE-P model is used in the viscoelastic fluid flow in the bend. The flow characteristics of viscoelastic fluid are discussed compared with that of a newtonian fluid.

关键词： non-newtonian flow viscoelastic fluid drag reduction bend flow LES LDV.

Simulating Two-Phase Viscoelastic flows Using Moving Finite Element Methods

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Communications in Computational Physics 2010年第2期7卷 333-349页

作者： Yubo Zhang Heyu Wang Tao Tang Department of Mathematics Hong Kong Baptist UniversityKowloon TongHong Kong Department of Mathematics Zhejiang UniversityHangzhouZhejiang 310027China

Phase-field models provide a way to model fluid interfaces as having finitethickness;the interface between two immiscible fluids is treated as a thin mixing layeracross which physical properties vary steeply but continuously. One of the main chal-lenges of this approach is in resolving the sharp gradients at the interface. In this paper,moving finite-element methods are used to simulate interfacial dynamics of two-phaseviscoelastic flows. The finite-element scheme can easily accommodates complex flowgeometry and the moving mesh strategy can cluster more grid points near the thin in-terfacial areas where the solutions have large gradients. A diffused monitor function isused to ensure high quality meshes near the interface. Several numerical experimentsare carried out to demonstrate the effectiveness of the moving mesh strategy.

关键词： Moving finite-element method two-phase flow viscoelastic flow non-newtonian flow