Peristaltic Motion with Nanofluid Characteristics

Abstract

Peristalsis is well-known activity for fluid transport in physiology. In this mechanism sinusoidal waves travel along the walls of tube like organs of human beings propelling the fluid contained within the tube in the direction of their propagation. In physiology the principle of peristalsis is seen in the transport of food through oesophagus, movement of chyme in intestines, urine transport from kidneys to bladder, bile transport in bile duct, vasomotion of blood vessels and many others. This mechanism has been adopted by the engineers in designing several industrial appliances including roller and fingers pumps and peristaltic pumps in heart lung and dialysis machines. Improvement in the heat transfer processes is core issue for the industrial and biological processes. Circulation of blood in the body causes the heat transfer amongst tissues. Therefore heat transfer mechanism amongst tissues and the effect of heat on tissues are common topics of interest. The efficiency of nuclear reactors and automobile engines depend on cooling system. Therefore thermal radiators are used to prevent engines from overheating due to friction. The ordinary fluids like water, ethylene glycol and engine oil etc. are used to cool various industrial devices by transforming heat away from the heat source. However, fluids having low thermophysical characteristics therefore minimizing the efficiency of the system. In order to overcome the limitation of the coolant processes, the nanosized particles are mixed in the ordinary fluids. Nanomaterials have unique thermophysical characteristics when compared to ordinary fluids. The homogenous mixtures of nanoparticles and base liquids are known as nanofluids. Novel concept of nanofluid greatly motivated the researchers due to its better thermal features, excellent stability, physical strength and minimal clogging. It is now established fact that the non-Newtonian materials are encountered in the physiological and engineering processes. Therefore viscous and non-Newtonian fluids are accounted in this thesis. Structure of thesis is as follows. Chapter one has literature review of relevant previous published work and relations for conservation of mass, momentum, energy and concentration. Tensor forms for Newtonian and non-Newtonian fluids (Sisko, Carreau-Yasuda and Powell-Eyring) are presented. Chapter two elaborates the peristaltic flow of nanofluid. Hall and Ohmic heating effects with temperature dependent viscosity are considered. Mixed convection and heat source/sink parameter are also taken. Resulting problem is solved via NDSolve technique under the lubrication approach. Material of this chapter is submitted for publication in Numerical methods for Partial differential equations. Chapter three addresses MHD peristaltic flow of nanofluid with variable viscosity. The nanofluid saturates a porous medium with variable porosity and permeability. Temperature dependent viscosity and Maxwell’s thermal conductivity models are adopted. Velocity and thermal slip conditions are also taken into examination. Simplified non-dimensional equations are numerically solved. Effects of important parameters on pressure gradient, velocity, temperature and heat transfer rate are studied. Outcomes of this chapter are submitted for publication in Numerical methods for Partial differential equations. Chapter four illustrates the entropy generation in peristaltic transport of nanomaterial with iron oxide. MHD and Joule heating. Energy equation further consists of heat source/sink and viscous dissipation. Velocity slip and temperature jump conditions are accounted. The data of this chapter is published in Journal of Thermal Analysis and Calorimetry 140 (2020) 789-797. Chapter five examines the Hall, Ohmic heating and velocity slip effects on the peristalsis of nanofluid. Convective boundary conditions and heat generation/absorption are considered to facilitate the heat transfer characteristics. Governing equations for the peristaltic flow through a curved channel are derived in curvilinear coordinates. The equations are numerically solved. The contents of this chapter are published in Journal of Central South University 26 (2019) 2543- 2553. Chapter six explores the thermophysical characteristics of nanofluid for mixed convective peristaltic motion in the presence of Joule heating. Analysis has been organized for Sisko fluid. Brownian motion and thermophoresis are used to examine the nanomaterial effects. Velocity and thermal slip conditions are utilized. Zero mass flux condition is imposed. Small Reynolds number and large wavelength arguments are employed. Governing problem is nonlinear in terms of both differential equation and boundary conditions. Numerical solution to incoming nonlinear problem is computed. Findings of this chapter is published in Journal of Thermal Analysis and Calorimetry (2020). Chapter seven illustrate the peristaltic activity of Sisko nano-liquid subject to Hall and Ohmic heating effects. Fluids saturating porous space is modelled using modified Darcy's law. Thermal radiation is also accounted. In addition, the analysis is carried out subject to thermal jump, velocity slip and zero mass flux condition. Numerical solution to the resulting nonlinear problem through lubrication approach is developed. The observations of this chapter are accepted in Journal of Thermal Analysis and Calorimetry (2020). Chapter eight communicates the numerical study for peristalsis of Carreau–Yasuda nanofluid in a symmetric channel. Constant magnetic field is applied. Modified Darcy’s law and nonlinear thermal radiation effects are considered. Viscous dissipation and Ohmic heating effects are present. Long wavelength and small Reynolds number are considered. Resulting nonlinear problems are solved numerically. The contents of this chapter are published in Journal of Thermal Analysis and Calorimetry 137 (2019) 1168-1177. Chapter nine addresses the flow of Carreau-Yasuda nanofluid in presence of mixed convection and Hall current. Effects of viscous dissipation, Ohmic heating and convective conditions are addressed. Zero nanoparticle mass flux condition is imposed. Wave frame analysis is employed. Coupled differential systems after long wavelength and low Reynolds number are numerically solved. The results of this chapter are published in Result in Physics 8 (2018) 168-1177. Chapter ten describes the peristaltic transport of magneto nanofluid in a symmetric channel. Carreau–Yasuda model is used to explore the shear thickening and shear thinning characteristics. Joule heating and viscous dissipation effects are included in the energy equation. Effects of slip velocity, temperature jump and zero mass flux boundary conditions for channel walls are further considered. Entropy generation and Bejan number are studied. The data of this chapter is published in Physica Scripta 95 (2020) 055804. Chapter eleven explores the influence of mixed convection, Hall effect and magnetic field on peristaltic motion of Powell-Eyring nanofluid in a symmetric channel. Energy equation includes the viscous dissipation, Ohmic heating and thermal radiation. Brownian motion and thermophoresis are considered to explore the nanofluid characteristics. Velocity slip, thermal jump and zero mass flux conditions are considered on the boundary wall. Further temperature dependent viscosity is taken into account. Lubrication approach is used to simplify the dimensionless form of governing equations. Final form of equations are solved numerically. Outcomes of this chapter are submitted for publication in International Communication in Heat and Mass Transfer.