Wavy Channel Research Articles

Erratum to: Mathematical modeling of magneto-peristaltic propulsion of a viscoelastic fluid through a complex wavy non-uniform channel: an application of hall device in bio-engineering domains

Erratum to: Mathematical modeling of magneto-peristaltic propulsion of a viscoelastic fluid through a complex wavy non-uniform channel: an application of hall device in bio-engineering domains

Mathematical modeling of magneto-peristaltic propulsion of a viscoelastic fluid through a complex wavy non-uniform channel: an application of hall device in bio-engineering domains

Applications of the Hall device into both the biological and engineering domains have been investigated in the current study. A complex peristaltic driven flow of a viscoelastic fluid is considered through a non-uniform regime having wavy walls under the magnetic and Hall effects. The physical influences of magnetic and Hall parameters on different rheological features of biomimetic propulsion in the wave frame are highlighted in details. Due to the complex nature of the flow regime, the curvilinear coordinates are used in the derivation of continuity and momentum equations. The flow analysis is based on creeping phenomena and long wavelength approximations. Analytical solutions of the governing equations are difficult to obtain due to complicated and complex mathematical form of partial differential equations. Numerical solutions of the governing equations are obtained with the help of the versatile BVP4C command in MATLAB software. The main objective of the current study is to observe the physical behavior of embedded parameters such as dimensionless radius of curvature, Hartmann number (magnetic parameter), Hall parameter, phase difference, non-uniform parameter, and viscoelastic (time relaxation and retardation) parameters on the axial velocity, stream function, pressure gradient, pumping, and trapping phenomena. Moreover, the comparison between viscous and viscoelastic fluids has been argued in detail through graphs. This research work provides comprehensive information about the magnetic and Hall devices, respectively, that are more productive to control the flow of biological fluids through the non-uniform nature of vessels. This study has numerous applications in micro-scale devices of biomedical and industrial domains, cooling systems in nuclear power stations, magnetic therapy, hydrology, physiological drug delivery systems, blood pumping, and micro devices used during surgical treatments.

Mathematical modeling of bio‐magnetic fluid bounded within ciliated walls of wavy channel

AbstractPeristaltic transport of couple stress fluid with heat transfer is investigated through flexible walls of the channel furnished with hair‐like structures. Locomotion of biological fluid is the result of the simultaneous propagation of metachronal waves (MCWs) and peristaltic waves. MCW emerges due to multi‐movement of cilia, while the elastic‐walls of the channel are responsible for the peristaltic wave. The two‐dimensional rheological flow experiences the resistive behavior of applied magnetic fields, besides, the role of viscous dissipation and entropy generation. A closed‐form solution is achieved for the nonlinear coupled differential equation, which is vetted through graphs. Finally, the theoretical analysis introduces the manufacture of a ciliate bronchial tube that can efficiently; remove mucus out of the lungs and bloodstream.

Numerical investigation of the effect of corrugation profile on the hydrothermal characteristics and entropy generation behavior of laminar forced convection of non-Newtonian water/CMC-CuO nanofluid flow inside a wavy channel

The force convection flow of non-Newtonian water/Carboxy-Methyl Cellulose (CMC)-CuO Nanofluid (NF) in three wavy channels and a straight channel was numerically investigated. The two dimensional governing equations were solved in the computational domain using the FLUENT software. The influence of Re and nanoparticle concentration (φ) on the pressure drop (ΔP), Nu, and global thermal and frictional entropy generation rates (Ṡg,th and Ṡg,f) were studied for different Re and φ values. The results showed that the influence of Re on the Nu is much higher than that of φ. The increasing of the Re and decreasing of φ, results in increasing the Nu for four channels of the study. Besides, the sinusoidal channel has the highest Nu as compared to the other channels. Also, the highest pressure drop and total global entropy generation rate were obtained for the trapezoidal channel.

A review on latest development in heat transfer through porous media in combination with nanofluids and wavy walls

Heat flow through porous media and different phenomenon in these media are studied widely in recent years due to their extraordinary applications in different fields of engineering, bio-engineering and energy systems etc. In this report, recent advances in the numerical investigation of completely or partial filled porous media alone or in combination with wavy walls and nanofluids/nanoparticles have been reviewed. The main emphasis of this is to review the theoretical and numerical aspects of the effect of position of porous insert, nanoparticle volume concentration and the amplitude of the waves associated with wavy channels on the Nusselt number, pressure drop, entropy generation and efficiency of heat transfer. The conditions which define the boundary for the use of LTE (Local thermal equilibrium) and LTNE (Local thermal nonequilibrium) equations for evaluation of the porous media have also been reviewed. The LTE equations were found to be appropriate for the systems in which the temperature different between the solid and fluid phase is very small whereas, if the temperature difference between the two is large, then only LTNE can be employed. The porous media along with wavy walls and nanofluid combinations was found to exhibit better results in terms of Nusselt number and heat transfer efficiency but to obtain bets results, minimum amplitude in case of wavy walls and volume concentration of nanoparticle concentration should be optimized.

Hydrodynamics and Sensitivity Analysis of a Williamson Fluid in Porous-Walled Wavy Channel

Hydrodynamics and Sensitivity Analysis of a Williamson Fluid in Porous-Walled Wavy Channel

A multi-domain shear-stress dependent diffusive model of cell transport-aided dialysis: analysis and simulation.

Kidney dialysis is the most widespread treatment method for end-stage renal disease, a debilitating health condition common in industrialized societies. While ubiquitous, kidney dialysis suffers from an inability to remove larger toxins, resulting in a gradual buildup of these toxins in dialysis patients, ultimately leading to further health complications. To improve dialysis, hollow fibers incorporating a cell-monolayer with cultured kidney cells have been proposed; however, the design of such a fiber is nontrivial. In particular, the effects of fluid wall-shear stress have an important influence on the ability of the cell layer to transport toxins. In the present work, we introduce a model for cell-transport aided dialysis, incorporating the effects of the shear stress. We analyze the model mathematically and establish its well-posedness. We then present a series of numerical results, which suggest that a hollow-fiber design with a wavy profile may increase the efficiency of the dialysis treatment. We investigate numerically the shape of the wavy channel to maximize the toxin clearance. These results demonstrate the potential for the use of computational models in the study and advancement of renal therapies.

Sensitivity Analysis of Micropolar Fluid Flow in a Porous Wavy Channel with Flow Rate Model

Sensitivity Analysis of Micropolar Fluid Flow in a Porous Wavy Channel with Flow Rate Model

Peristaltic Carreau-Yasuda nanofluid flow and mixed heat transfer analysis in an asymmetric vertical and tapered wavy wall channel

In this study, two-phase asymmetric peristaltic Carreau-Yasuda nanofluid flow in a vertical and tapered wavy channel is demonstrated and the mixed heat transfer analysis is considered for it. For the modeling, two-phase method is considered to be able to study the nanoparticles concentration as a separate phase. Also it is assumed that peristaltic waves travel along X-axis at a constant speed, c. Furthermore, constant temperatures and constant nanoparticle concentrations are considered for both, left and right walls. This study aims at an analytical solution of the problem by means of least square method (LSM) using the Maple 15.0 mathematical software. Numerical outcomes will be compared. Finally, the effects of most important parameters (Weissenberg number, Prandtl number, Brownian motion parameter, thermophoresis parameter, local temperature and nanoparticle Grashof numbers) on the velocities, temperature and nanoparticles concentration functions are presented. As an important outcome, on the left side of the channel, increasing the Grashof numbers leads to a reduction in velocity profiles, while on the right side, it is the other way around.

Computational analysis of hybrid nanofluid enhanced heat transfer in cross flow micro heat exchanger with rectangular wavy channels

The current paper provides a three-dimensional computational analysis of hybrid nanofluid enhanced heat transfer in cross flow micro heat exchanger with rectangular wavy channels. This micro heat exchanger is assumed to be well insulated from its surrounding and made respectively of five top and five bottom channels. The hot and cold nanofluids flow through the upper and lower cross channels, respectively. This analytical investigation has been carried out using the finite element method with a wide range of governing parameters such as the flow velocity (5 mm/s ≤ u ≤ 100 mm/s), the wave number (0 ≤ N ≤ 20) and the nanoparticles concentration (0 ≤ ϕ ≤ 0.05). It was concluded that an adequate choice of flow velocity and nanoparticles volume fraction can minimize the heat exchanger size and the addition of nanoparticles has significant effect only with high velocities (u ≥ 50 mm/s). Moreover, it was revealed that a trade-off between the relevant controlling parameters is required to ensure an optimal efficiency. The highest heat exchanger efficiency was achieved with a wave number N = 8, a nanoparticles concentration ϕ = 0.05 and an inlet velocity u = 50 mm/s.

Intensification of convective heat transfer in new shaped wavy channel configurations

The paper presents the specific wavy heat exchange surfaces in order to intensify convective heat transfer in the channel. The study is focused on the analysis of local and average heat transfer coefficients and Nusselt numbers by experimental method of the holographic interferometry and numerical simulations. The results are presented for temperatures of the heat exchange surfaces Ts = 318.15 K, 328.15 K, 338.15 K, and 348.15 K, Reynolds numbers Re = 1386–4203, and height between the surfaces H = 30, 35, 40, 45, and 50 mm. New correlating equations for average Nusselt number for the in-line and the offset wavy channels are determined. The total heat transfer and pressure drop j/f and thermal performance η are calculated for the wavy channels compared with the smooth one. It is observed that the offset wavy channel achieves a higher j/f values compared with the in-line wavy channel for all H and Ts values. The thermal performance η increases with Re and decreases with height H. The offset wavy channel achieves higher thermal performance η by 5.7%–15.7% when changing Re and H compared with the in-line one.

Numerical investigation and design optimization of a novel polymer heat exchanger with ogive sinusoidal wavy tube

In this paper, a novel polymer bare-tube heat exchanger (BTHX) with an ogive tube shape and a sinusoidal wavy channel is proposed and investigated for the liquid-to-gas application. The thermal-hydraulic performance of the proposed polymer BTHX is calculated using a validated computational fluid dynamics (CFD) simulation model, and the performance is optimized by setting nine independent design variables. A selective-series CFD method with an approximation-assisted optimization technique is developed for the multi-objective optimization to reduce the computational time. As a result, the thermal-hydraulic performance of the optimized novel polymer BTHX shows 91.5% and 134.9% of that of the target aluminum louvered-fin micro-channel heat exchanger (MCHX), respectively. This is mainly due to the improved air-side heat transfer coefficient of the proposed polymer BTHX by 70.2% compared to the target aluminum MCHX. Compared to the recent teardrop-shaped polymer BTHX, the thermal-hydraulic performance of the proposed BTHX is significantly improved. Regarding the polymer thermal conductivity, it is found that the thermal performance degradation can be minimized with at least 8.0 W·m−1·K−1 of the thermal conductivity. The flow field of the proposed polymer BTHX is also discussed and shows that the unique structure of the sinusoidal wavy tube can reduce the air-side pressure drop and promote the mixing of the air flow, thereby improving the air-side convective heat transfer.

Peristaltically driven flow of hybrid nanofluid in a sinusoidal wavy channel with heat generation

The present analysis is reported to analyze the hybrid nanofluid (SiO 2 − CNT/H 2 O) flow as peristaltic transport under the influence of heat generation/absorption in a sinusoidal wavy channel. We have expressed the non-dimensional equations into two dimensional coordinate system by using vary long wavelength (δ < 1) and low Reynolds number assumptions. The non-dimensional hybrid nanofluid (SiO 2 − CNT/H 2 O) equations are solved approximately by using well known perturbation approach. The numerical solutions for temperature and two dimensional peristaltic flow are obtained by using Mathematica software. The obtaining solutions for temperature and peristaltic transport are expressed graphically with help of Matlab software. The graphical results show that pressure rise, temperature profile and pressure gradient of hybrid nanofluid (SiO 2 − CNT/H 2 O) flow increases due to increase of heat generation. The pressure rise and pressure gradient of hybrid nanofluid decreases due to increase of phase difference ϑ. Furthermore, pressure gradient and pressure rise of SiO 2 − CNT/H 2 O hybrid nanofluid also decreases by increase in channel width. The streamlines for peristaltic transport are also elucidated in present analysis. The streamlines show that bolus size increases due to increase of amplitude but decreases by increase of heat generation.

Viscous Dissipation Effect on Heat Transfer Through Nano Fluid in a Vertical Wavy Channel with Travelling Thermal Wave

The effect of viscous dissipation on heat transfer through nano-fluid in a vertical wavy channel filled with porous media has been studied. The consequential differential equations are simplified by the R-K method of 6th order. The numerical obtained results are shown in the graphs. The significant results of fluid flow and heat transfer rate and its properties are shown graphically. Nusslet values are calculated a for varying the governing parameters φ Da, Gr, ε, Ec and the remaining parameters are to be constants.

Efficient design of a wavy channel embedded with porous media for solar air heating

ABSTRACT In this experimental thermal performance investigation, we present a solar air heater design exhibiting a wavy channel embedded with porous media to illustrate the enhanced fluid mixing and heat transfer area, and consequently high thermal performance. In this design, two wavy plates form the air flow channel and wiremesh as a porous media of high porosity is inserted in the wavy channel to maintain the channel porosity. Results of the investigation revealed promising scope for thermal performance enhancement. Thermal and thermohydraulic efficiency of 38–93% and 38–89%, respectively, is obtained for the investigated range of Reynolds number and channel porosity (. Moreover, the obtained result of thermal and thermohydraulic efficiency for 97% channel porosity is 27% and 24%, respectively, high compared to 100% channel porosity. As a part of this work, we also presented the developed correlations for Nusselt number and friction factor to predict the thermal performance of wavy absorber plate embedded with porous media and the effect of Darcy number on the thermal performance.

Optimal design of a converging diverging channel for convective heat transfer enhancement in fully developed turbulent air flow

The optimization operation has been performed with ANSYS Response Surface Optimization Tool to find optimum channel geometry for converging-diverging channels. Steady state, three dimensional, turbulence, viscous, compressible, single-phase Newtonian flow is assumed through the channel with rectangular cross section. In the study, output parameters have been selected as Colburn factor and Darcy friction factor. Effects of channel width, wavelength and amplitude of converging-diverging channel on output parameters have been examined and non-dimensionless results have been obtained for optimal geometries for three different Reynolds numbers (Re = 4400, 5600 and 6700). To analyze the thermal-hydraulic performance of the optimum wavy channel, thermal performance factors (TPF) are calculated. Results showed that optimized channel is more efficient than straight channel, TPF values for optimized channel were ranged from 1.7 to 1.4 over the range of Re studied.

Entropy and thermal performance analysis of PCM melting and solidification mechanisms in a wavy channel triplex-tube heat exchanger

This paper aims to perform the entropy analysis and thermal performance evaluation of a wavy-channels triplex-tube latent heat storage heat exchanger (LHSHE) during melting and solidification mechanisms. The system with different wave amplitudes was examined for different temperatures and Reynolds numbers of the heat transfer fluid (HTF). Water is passed in the inner and outer tubes in opposite directions and the PCM is placed in the middle tube. The heat exchanger was analyzed based on the temperature, liquid fraction and velocity of the PCM as well as thermal (ST‴) and frictional (Sf‴) entropy generation rates. The results show that for a higher wave amplitude, shorter melting and solidification times are achieved. Both frictional and thermal entropy generation rates increase to the maximum values and then decrease during the melting and solidification. The frictional entropy generation rate reaches almost zero quickly during the solidification. For both melting and solidification, the magnitude of ST‴ is significantly higher than Sf‴ in the phase change problem. The maximum values of ST‴ are 0.05 and 0.13 W/Km3 for the melting and solidification mechanisms, respectively, for the dimensionless wave amplitude of 0.3. The results show the crucial role of entropy generation on the performance of the LHSHE.

Fluid Flow and Heat Transfer in Wavy Channel Consisting of Walls with Unequal Amplitudes

Fluid Flow and Heat Transfer in Wavy Channel Consisting of Walls with Unequal Amplitudes

Effect of Hall Currents on Convective Heat and Mass Transfer Flow of a Viscous Electrically Conducting Fluid in A Nonuniformly Heated Vertical Channel with Radiation

In the present document we inspect the deportation study of heat and mass transfer flow of a viscous electrically conducting fluid in a vertical wavy channel under the influence of an inclined magnetic fluid with heat generating sources. The walls of the channels are perpetuated at constant temperature and concentration. The equations reign over the flow heat and concentration are solved by employing perturbation technique with a slope d of the wavy wall. The velocity, temperature and concentration distributions are investigated for a different value of Grashof number Hartmann number, Buoyancy ratio etc. The rate of heat and mass transfer are numerically estimated for a different variation of the governing parameters. It is found that higher the Lorentz force lesser the axial velocity in the flow region. An increase in the Hall parameter (m) enhances the axial velocity.

Entropy analysis in the Rabinowitsch fluid model through inclined Wavy Channel: Constant and variable properties

Entropy production in a system affects the efficiency of the system because it minimizes the output of the system. For the better performance of the system, it is very important to minimize the entropy production. Entropy generation is always observed in any irreversible process while it remains constant in any reversible process. Second law of thermodynamics play an important in the optimization of entropy generation rate. The main objective of this investigation is to minimize the entropy production through an inclined channel filled with Rabinowitsch fluid. For the better results, we will visually show the entropy generation under the account of two different cases. In the first case, we will choose the viscosity and thermal conductivity of the fluid as a constant and for the second case, viscosity and thermal conductivity will be treated as a variable. Further, the comparison of both the cases will be given under the effects of fluidic parameters. The Exact solutions of velocity and energy equations are obtained for the constant properties model with the help of MATHEMATICA software, while for the second model, the solution of the velocity profile is obtained in terms of analytic form with the help of MATHEMATICA version 11.0. The regular perturbation method is selected to solve the energy equation due to its complexity and presented the temperature profile in the form of an approximate analytical solution. In the end, the analytical solutions for total entropy and Bejan number for both cases are obtained with the help of Mathematica version 11.0. A small amount of entropy is observed at the bottom of the channel and maximum entropy is noted at the ciliated walls under the effect of Brinkman number. Maximum value of the entropy number is observed for the case of variable properties as compared to the uniform properties, which showed that the variable liquid properties are the best choice to minimize the entropy of the system and to increase the efficiency of the system.