Fully-developed pipe and planar flows of multimode viscoelastic fluids

Cruz, D. O. A.; Pinho, F.T.

doi:10.1016/j.jnnfm.2006.09.001

Cited by 23 publications

(10 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this study, the values of the adjustable parameters in the EPTT model are selected with respect to the research of Cruz and Pinho [36] ( = 0.02, = 0.04 ). Also, the previous studies proved that the values of these parameters must be small to have a good agreement with empirical data [37].…”

Section: Governing Equationsmentioning

confidence: 99%

Effects of fluid inertia and elasticity and expansion angles on recirculation and thermal regions of viscoelastic flow in the symmetric planar gradual expansions

Shahbani-Zahiri

Shahmardan

Norouzi

2018

J Braz. Soc. Mech. Sci. Eng.

View full text Add to dashboard Cite

The formation and growth of symmetric and asymmetric recirculation regions play an important role in the viscous dissipations, temperature distribution, and heat transfer rate. In this study, the inertial and non-isothermal flow of viscoelastic fluid has been simulated in the planar channel with a 1:3 symmetric gradual expansion for different Reynolds and elasticity numbers at three expansion angles of 30°, 45°, and 60°. Also, the thermal boundary condition of constant temperature has been used on the walls, and the constitutive equation of exponential Phan Thien-Tanner has been employed for modeling the polymeric stresses of the viscoelastic fluid. Due to the significant effect of temperature on the properties of the viscoelastic fluid, and the role of viscous dissipation in heat generation, the fluid properties are considered temperature dependent, and the terms of viscous dissipation are considered in the energy equation. The main purpose of current study is to investigate the effects of fluid inertia and elasticity and the expansion angles on the flow pattern, heat transfer characteristics, and viscous dissipation of inertial viscoelastic flow in the planar channel with gradual expansions. Therefore, the streamlines, length of vortices, isothermal lines, total viscous dissipations, and local and mean Nusselt numbers (Nu) have been examined inside the channel expansion for different Reynolds and elasticity numbers in the range of 10 ≤ Re ≤ 100 and 0.01 ≤ El ≤ 2. The results show that the maximum values of local Nusselt numbers are enhanced by increasing the Reynolds and elasticity numbers and the expansion angle for the hydrodynamically and thermally developing conditions.

show abstract

Section: Governing Equationsmentioning

confidence: 99%

Effects of fluid inertia and elasticity and expansion angles on recirculation and thermal regions of viscoelastic flow in the symmetric planar gradual expansions

Shahbani-Zahiri

Shahmardan

Norouzi

2018

J Braz. Soc. Mech. Sci. Eng.

View full text Add to dashboard Cite

show abstract

“… Comparison with literature data: ( a ) steady viscoelastic flow in a pipe [ 42 ], ( b ) swirl decay in a pipe (water, K = 1, Re = 98.8) [ 43 ]. …”

Section: Figurementioning

confidence: 99%

The Viscoelastic Swirled Flow in the Confusor

et al. 2021

View full text Add to dashboard Cite

A two-dimensional mathematical model for a steady viscoelastic laminar flow in a confusor was developed under the condition of swirled flow imposed at the inlet. Low density polyethylene was considered as a working fluid. Its behavior was described by a two-mode Giesekus model. The proposed mathematical model was tested by comparing it with some special cases presented in the literature. Additionally, we propose a system of equations to find the nonlinear parameters of the multimode Giesekus model (mobility factor) based on experimental measurement. The obtained numerical results showed that in a confusor with the contraction rate of 4:1, an increase in the swirl intensity at Wi < 5.1 affects only the circumferential velocity, while the axial and radial velocities remain constant. The distribution pattern of the first normal stress difference in the confusor is qualitatively similar to the one in a channel with abrupt contraction, i.e., as the viscoelastic fluid flows in the confusor, the value of N1 increases and reaches a maximum at the end of the confusor. Dimensionless damping coefficients of swirl are used to estimate the swirl intensity. The results show that the swirl intensity decreases exponentially.

show abstract

“…Where the parameters of e and λ are extensibility property and relaxation time, respectively. In the present study, the values of the adjustable parameters and extensibility are considered to be 0.04 x = and 0.02 e = (according to the study of Cruz & Pinho [15]). In this study, the used significant dimensionless groups are defined as follows:…”

Section: Equationsmentioning

confidence: 99%

Effects of Elasticity Number on the Heated Flow of Viscoelastic Fluid inside Planar Channel with a Symmetric Abrupt Expansion

Zahiri¹,

Shahmardan²,

Norouzi³

2017

ujas

View full text Add to dashboard Cite

In this work, we have numerically studied the heat transfer of viscoelastic fluid flow inside a planar channel with 1:3 abrupt expansion. For modeling rheological behavior of non-creeping flow related to the viscoelastic fluid which includes both the effects of shear-thinning and elasticity, the constitutive equation of exponential Phan Thien-Tanner (EPTT) is used. Also, thermal boundary condition of constant temperature at the walls and inlet of channel with internal heat generated by the viscous dissipation are considered. Because of high temperature differences in the current study, the fluid properties such as fluid viscosity, relaxation time, specific heat capacity and thermal conductivity have a function of temperature. For coupling the variables of velocity, pressure and temperature, the PISO algorithm is employed and finite volume method (FVM) imposed on the collocated grid to discretize the governing equations. The main propose of the present study is to examine the effects of elastic property on the size of recirculation regions, temperature distribution, local and mean Nusselt numbers.

show abstract

Fully-developed pipe and planar flows of multimode viscoelastic fluids

Cited by 23 publications

References 26 publications

Effects of fluid inertia and elasticity and expansion angles on recirculation and thermal regions of viscoelastic flow in the symmetric planar gradual expansions

Effects of fluid inertia and elasticity and expansion angles on recirculation and thermal regions of viscoelastic flow in the symmetric planar gradual expansions

The Viscoelastic Swirled Flow in the Confusor

Effects of Elasticity Number on the Heated Flow of Viscoelastic Fluid inside Planar Channel with a Symmetric Abrupt Expansion

Contact Info

Product

Resources

About