A mathematical study is described to examine the concurrent influence of thermal radiation and thermal wall slip on the dissipative magnetohydrodynamic electro‐osmotic peristaltic propulsion of a viscous nanoliquid in an asymmetric microchannel under the action of an axial electric field and transverse magnetic field. Convective boundary conditions are incorporated in the model and the case of forced convection is studied, that is, thermal and species (nanoparticle volume fraction) buoyancy forces neglected. The heat source and sink effects are also included and the diffusion flux approximation is employed for radiative heat transfer. The transport model comprises the continuity, momentum, energy, nanoparticle volume fraction, and electric potential equations with appropriate boundary conditions. These are simplified by negating the inertial forces and invoking the Debye–Hückel linearization. The resulting governing equations are reduced into a system of nondimensional simultaneous ordinary differential equations, which are solved analytically. Numerical evaluation is conducted with symbolic software (MATLAB). The impact of different control parameters (Hartmann number, electro‐osmosis parameter, slip parameter, Helmholtz–Smoluchowski velocity, Biot numbers, Brinkman number, thermal radiation, and Prandtl number) on the heat, mass, and momentum characteristics (velocity, temperature, Nusselt number, etc) are presented graphically. Increasing Brinkman number is found to elevate temperature magnitudes. For positive Helmholtz–Smoluchowski velocity (reverse axial electrical field) temperature is strongly reduced, whereas for negative Helmholtz–Smoluchowski velocity (aligned axial electrical field), it is significantly elevated. With increasing thermal slip, nanoparticle volume fraction is also increased. Heat source elevates temperatures, whereas heat sink depresses them, across the microchannel span. Conversely, heat sink elevates nanoparticle volume fraction, whereas heat source decreases it. Increasing Hartmann (magnetic) parameter and Prandtl number enhance the nanoparticle volume fraction. Furthermore, with increasing radiation parameter, the Nusselt number is reduced at the extremities of the microchannel, whereas it is elevated at intermediate distances. The results reported provide a good insight into biomimetic energy systems exploiting electromagnetics and nanotechnology, and, furthermore, they furnish a useful benchmark for experimental and more advanced computational multiphysics simulations.

Nanofluids have shown significant promise in the thermal enhancement of many industrial systems. They have been developed extensively in energy applications in recent years. Solar energy systems are one of the most promising renewables available to humanity and these are increasingly being redesigned to benefit from nanofluids. Most designs of solar collectors involve fixed (rigid) geometries which may be cylindrical, parabolic, tubular or flat-plate types. Modern developments in biomimetics have identified that deformable conduit structures may be beneficial for sustainable energy systems. Motivated by these aspects, in the current work we present a novel model for simulating a biomimetic peristaltic solar magnetohydrodynamic nanofluid-based pump. The working fluid is a magnetized nanofluid which comprises a base fluid containing suspended magnetic nano-particles. The novelty of the present work is the amalgamation of biomimetics (peristaltic propulsion), magnetohydrodynamics and nanofluid dynamics to produce a hybrid solar pump system model. Heat is transferred via distensibility of the conduit in the form of peristaltic thermal waves and buoyancy effects. An externally applied magnetic field achieves the necessary circuit design for generating Lorentzian magnetic body force in the fluid. A variable viscosity modification of the Buongiorno nanofluid model is employed which features thermophoretic body force and Brownian dynamic effects. To simulate solar loading conditions a thermal radiative flux model is also deployed. An asymmetric porous channel is investigated with multiple amplitudes and phases for the wall wavy motion. The channel also contains a homogenous, isotropic porous medium which is simulated with a modified Darcy model. Heat generation/absorption effects are also examined. The electrically-conducting nature of the nanofluid invokes magnetohydrodynamic effects. The moving boundary value problem is normalized and linearized using the lubrication approach. Analytical solutions are derived for axial velocity, temperature and nanoparticle volume fraction. Validation is conducted with Maple numerical quadrature. Furthermore, the salient features of pumping and trapping phenomena discourse briefly. The observations demonstrate promising features of the solar magnetohydrodynamic peristaltic nanofluid pump which may also be exploited in spacecraft applications, biological smart drug delivery etc.

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The peristaltic flow of a viscoelastic fluid in the tapered microchannel with variable viscosity is investigated. This study is reinvigorated by discovering fluid dynamic in peristaltic motion as signified by biological flows, pharmacodynamics and gastro-intestinal motility enhancement. The microchannel non-uniform and asymmetry is developed by choosing a peristaltic wave train on the wall with different amplitudes and phases. The flow analysis has been arisen for low Reynolds number and long wavelength case. The solutions for stream function, axial velocity and pressure gradient are obtained. The effects of pertinent parameters on the average pressure rise per wavelength are investigated by means of numerical integration. The axial velocity and phenomena of trapping are further discussed.

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