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An earthworm moves by peristaltic crawling which brings a large surface into contact during motions and requires less space than other mechanisms. A peristaltic crawling is suitable for moving in excavated space by an anterior (front) of a robot. Therefore, a peristaltic crawling robot is useful for an underground explorer. The purpose of this paper is to develop a peristaltic crawling robot with several parallel links and compare with motion of an actual earthworm. Then we had some experiments on a plane surface and in a tube, and in vertical perforated dirt.

The proposed robot, which consists of several parallel mechanisms, has four units for being controlled in 3‐DOF. A unit expands in a radial direction when it contracts to increase the friction between the unit and surroundings. Dustproof covering is attached for preventing dirt from getting inside units. Locomotion mechanism is as the same as an actual earthworm's peristaltic crawling. The robot makes an anterior unit contract, and then the contraction propagates towards the posterior (rear). Therefore, it requires no more space than that of an excavation part on the front of the robot.

It was found that three units of robot consists of several parallel mechanisms had wide range of manipulation; four units of robot moves with peristaltic crawling compared with motion of an actual earthworm. It was confirmed that the robot could turn on a plane surface and move upward and downward in a vertical pipe. Finally, the robot could move in vertical perforated dirt faster than in a pipe.

The robot is designed with several parallel links and equipped with dustproof covering. The locomotion of an actual earthworm is videotaped and analysed for comparing with the analysed movements of the robot. It was confirmed the robot could move with peristaltic crawling and turn on a plane surface. In addition, it was confirmed that some experiments were done in a narrow pipe and in vertical perforated dirt.

The main purpose of this paper is to study the effect of heat transfer on the peristaltic flow of a magnetohydrodynamic Walters B fluid through a porous medium in an inclined asymmetric channel.

The approximate analytical solutions of the governing partial differential equations are obtained using the regular perturbation method by taking wave number as a small parameter. The solutions for the pressure difference and friction forces are evaluated using numerical integration.

It is noticed that the pressure gradient and pressure difference are increasing functions of inclination angle and Grashof number. The temperature and heat transfer coefficients both increase with increase in inclination angle, Darcy number, Grashof number and Prandtl number. Increase in Hartmann number and phase difference decreases the size of trapped bolus.

The problem is original, as no work has been reported on the effect of magnetohydrodynamics on the peristaltic flow of a Walters B fluid through a porous medium in an inclined asymmetric channel with heat transfer.

The peristaltic motion for Carreau fluid by means of an infinite train of sinusoidal waves traveling along the walls of a circular cylindrical flexible tube is investigated. The fluid is subjected to a constant transverse magnetic field. A perturbation solution is obtained for the case in which Weissenberg number is small. The effects of Hartmann number, Weissenberg number, power‐law index and amplitude ratio on the pressure rise and the friction force are discussed. The trapping limit and the trapping occurrence region at the centerline decrease by increasing Hartmann number but they are independent approximately of Weissenberg number and power‐law index.

The purpose of this paper is to investigate the peristaltic flow of an incompressible Newtonian fluid in a channel with compliant walls. The effects of rotation and heat and mass transfer are also taken into account. The governing equations of two dimensional fluid have been simplified under long wavelength and low Reynolds number approximation. An exact solutions is presented for the stream function, temperature, concentration field, velocity and heat transfer coefficient.

The effect of the concentration distribution, heat and mass transfer and rotation on the wave frame are analyzed theoretically and computed numerically. Numerical results are given and illustrated graphically in each case considered. Comparison was made with the results obtained in the presence and absence of rotation and heat and mass transfer.

The results indicate that the effect of the permeability and rotation are very pronounced in the phenomena.

The objective of the present analysis is to analyze the effects of rotation, heat and mass transfer and compliant walls on the peristaltic flow of a viscous fluid.

The purpose of this paper is to study the peristaltic flow of a Jeffrey fluid in an asymmetric channel, subjected to gravity field and rotation in the presence of a magnetic field. The channel asymmetry is produced by choosing the peristaltic wave train on the walls to have different amplitude and phase. The flow is investigated in a wave frame of reference moving with the velocity of the wave. Involved problems are analyzed through long wavelength and low Reynolds number.

The analytical expressions for the pressure gradient, pressure rise, stream function, axial velocity and shear stress have been obtained. The effects of Hartmann number, the ratio of relaxation to retardation times, time-mean flow, rotation, the phase angle and the gravity field on the pressure gradient, pressure rise, streamline, axial velocity and shear stress are very pronounced and physically interpreted through graphical illustrations. Comparison was made with the results obtained in the asymmetric and symmetric channels.

The results indicate that the effect of the Hartmann number, the ratio of relaxation to retardation times, time-mean flow, rotation, the phase angle and the gravitational field are very pronounced in the phenomena.

In the present work, the authors investigate gravity field, and rotation through an asymmetric channel in the presence of a magnetic field has been analyzed. It also deals with the effect of the magnetic field and gravity field of peristaltic transport of a Jeffrey fluid in an asymmetric rotating channel.

This article aims to describe the effect of an endoscope and heat transfer on the peristaltic flow of a Jeffrey fluid through the gap between concentric uniform tubes.

The mathematical model of the present problem is carried out under long wavelength and low Reynolds number approximations. Analytical solutions for the velocity, temperature profiles, pressure gradient and volume flow rate are obtained.

The results indicate that the effect of the wave amplitude, radius ratio, Grashof number, the ratio of relaxation to retardation times and the radius are very pronounced in the phenomena. Also, a comparison of obtaining an analytical solution against previous literatures shows satisfactory agreement.

Analytical solutions for the velocity, temperature profiles, pressure gradient and volume flow rate are obtained. Numerical integration is performed to analyze the pressure rise and frictional forces on the inner and outer tubes.

Numerous researchers have probed the peristaltic flows because of their immense usage in industrial engineering, biomedical engineering and biological sciences. However, the investigation of peristaltic flow in two-phase fluid of a rotating frame in the presence of a magnetic field has not been yet discussed. Therefore, to fulfill this gap in the existing literature, this paper will explicate the peristaltic flow of two-phase fluid across a rotating channel with the effect of wall properties in the presence of a magnetic field. The purpose of this study is to investigate the two-phase velocity distribution and rotation parameter when magneto-hydrodynamics is applied.

The constituent equations are solved under the condition of low Reynolds number and long wavelength. The exact method is used to attain the subsequent equations and a comprehensive graphical study for fluid phase, particulate phase velocity and flow rates are furnished. The impacts of pertinent parameters, magnetic field and rotation are discussed in detail.

It is witnessed that the velocity profile of particulate phase gets higher values for the same parameters as compared to the fluid phase velocity. Moreover, the axial velocity increases with different values of particle volume fraction, but in case of magnetic field and rotation parameter, it shows the opposite behavior.

The outcomes of study have viable industrial implementations in systems comprising solid-liquid based flows of fluids involving peristaltic movement.

The investigation of peristaltic flow in two-phase fluid of a rotating frame in the presence of a magnetic field has not been yet discussed. Therefore, to fulfill this gap, the present study will explicate the peristaltic flow of two-phase fluid across a rotating channel with the effect of wall properties in the presence of magnetic field.

The purpose of this paper is to predict the effects of magnetic field, heat and mass transfer and rotation on the peristaltic flow of an incompressible Newtonian fluid in a channel with compliant walls. The whole system is in a rotating frame of reference.

The governing equations of two-dimensional fluid have been simplified under long wavelength and low Reynolds number approximation. The solutions are carried out for the stream function, temperature, concentration field, velocity and heat transfer coefficient.

The results indicate that the effects of permeability, magnetic field and rotation are very pronounced in the phenomena. Impacts of various involved parameters appearing in the solutions are carefully analyzed.

The effect of the concentration distribution, heat and mass transfer and rotation on the wave frame is analyzed theoretically and computed numerically. Numerical results are given and illustrated graphically in each case considered. A comparison was made with the results obtained in the presence and absence of rotation, magnetic field and heat and mass transfer.

Ohmic heating generates temperature with the help of electrical current and resists the flow of electricity. Also, it generates heat rapidly and uniformly in the liquid matrix. Electrically conducting biofluid flows with Ohmic heating have many biomedical and industrial applications. The purpose of this study is to provide the significance of the effects of Ohmic heating and viscous dissipation on electrically conducting Casson nanofluid flow driven by peristaltic pumping through a vertical porous channel.

In this analysis, the non-Newtonian properties of fluid will be characterized by the Casson fluid model. The long wavelength approach reduces the complexity of the governing system of coupled partial differential equations with non-linear components. Using a regular perturbation approach, the solutions for the flow quantities are established. The fascinating and essential characteristics of flow parameters such as the thermal Grashof number, nanoparticle Grashof number, magnetic parameter, Brinkmann number, permeability parameter, Reynolds number, Casson fluid parameter, thermophoresis parameter and Brownian movement parameter on the convective peristaltic pumping are presented and thoroughly addressed. Furthermore, the phenomenon of trapping is illustrated visually.

The findings indicate that intensifying the permeability and Casson fluid parameters boosts the temperature distribution. It is observed that the velocity profile is elevated by enhancing the thermal Grashof number and perturbation parameter, whereas it reduces as a function of the magnetic parameter and Reynolds number. Moreover, trapped bolus size upsurges for greater values of nanoparticle Grashof number and magnetic parameter.

There are some interesting studies in the literature to explain the nature of the peristaltic flow of non-Newtonian nanofluids under various assumptions. It is observed that there is no study in the literature as investigated in this paper.

This paper aims to investigate the consequence of the combined impacts of an induced magnetic field and thermal radiation on peristaltic transport of a Carreau nanofluid in a vertical tapered asymmetric channel. The model applied for the nanofluid comprises the effects of Brownian motion and thermophoresis.

The governing equations have been simplified under the widespread assumption of long-wavelength and low-Reynolds number approximations. The reduced coupled nonlinear equations of momentum and magnetic force function have also been solved analytically using the regular perturbation method.

The physical features of emerging parameters have been discussed by drawing the graphs of velocity, temperature, nanoparticle concentration profile, magnetic force function, current density, heat transfer coefficient and stream function. It has been realized that the magnetic force function is increased with the increase of Hartmann number, magnetic Reynolds number and mean flow rate.

It may be first paper in which the effect of induced magnetic field on peristaltic flow of non-Newtonian nanofluid in a tapered asymmetric channel has been studied.