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In classical continuum mechanics, a monolithic Eulerian formulation is used for numerically solving fluid–structure interaction (FSI) problems in the frame of a physically deformed configuration. This numerical approach is well adapted to large-displacement fluid–structure configurations where velocities of solids and fluids are computed all at once in a single variational equation. In the recent past, a monolithic Eulerian formulation for solving FSI problems of finite deformation to study the different physical features of fluid flow has been employed. Almost all the current studies use a classical framework in their approach. Despite producing decent results, such methods still need to be appropriately configured to generate exceptional results. Recently, a number of researchers have used a non-classical framework in their approach to analyze several physical problems. Therefore, in this paper, a monolithic Eulerian formulation is employed for solving FSI problems in a non-classical framework to study the micro-structural characteristics of fluid flow by validating the results with classical benchmark solutions present in the literature. In this respect, the Cosserat theory of continuum is considered where a continuum of oriented rigid particles has, in addition to the three translational degrees of freedom of classical continuum, three micro-rotational degrees of freedom. The mathematical formulation of model equations is derived from the general laws of continuum mechanics. Based on the variational formulation of the FSI system, we propose the finite element method and semi-implicit scheme for discretizing space and time domains. The results are obtained by computing a well-known classical FSI benchmark test problem FLUSTRUK-FSI-3* with FreeFem++. The results of the study indicate that the increase in micro-rotational viscosity μr leads to significantly large micro-rotations in fluid flow at the micro-structural level. Further, it is found that the amplitude of oscillations is related inversely to the material parameters c1 and μr while the increase in c1 stabilizes the amplitude of oscillations relatively more quickly than increasing μr The color snapshots of the numerical results at different times during the computer simulations and general conclusions drawn from the results are presented.

In this article, we study heat transfer enhancement of water based nanofluids with application to automotive radiators. In this respect, we consider here three types of different nanoparticles viz. copper oxide (CuO), Titanium dioxide (TiO2) and Aluminum oxide (Al2O3). The dynamics of the flow in a radiator is governed by set of partial differential equations (PDEs) along with boundary conditions which are formulated. Suitable similarity transformations are utilized to convert the PDEs into their respective system of coupled nonlinear ordinary differential equations (ODEs). The boundary value problem is solved using Shooting method embedded with Runge-Kutta-Fehlberg (RK-5) numerical scheme. Effects of different physical parameters are studied on profiles of velocity and temperature fields at boundary. In addition, influence of nanoparticle concentration factor on the local coefficient of skin-friction and Nusselt number is analyzed. We conclude that water based nanofluids with copper oxide nano-particles have a much higher heat transfer rate than the Al2O3-water and TiO2-water nanofluids. Moreover, larger the concentration of the CuO nanoparticles in the base fluid higher is the heat transfer rate of CuO-water nanofluid.

In this article, a non-Fourier approach to model the heat transfer phenomenon in nanofluids having application to automotive industry is studied. In this respect, a recently proposed hyperbolic heat flux equation is embedded into the heat energy equation and thereby incorporating the effect of thermal relaxation time. Nanofluids are formed by considering copper oxide (CuO), Titanium dioxide (TiO2) and Aluminum oxide (Al2O3) nano-solid particles in the base fluid. The flow governing system of PDEs along with boundary conditions is transformed into its respective coupled system of nonlinear ODEs using suitable similarity functions. Runge-Kutta-Fehlberg (RK-5) numerical scheme embedded with shooting method is implemented and used to solve the obtained boundary value problem. Numerical simulations are performed and tabulated to analyze the influence of solid volume fraction on local coefficient of skin-friction and Nusselt number. A comparison is made between the results by Fourier and present heat flux model. We conclude that the presented new approach is more general and thus allows predicting the influence of thermal relaxation time on the heat transfer characteristics. Moreover, consideration of present model over the Fourier model helps to predict the actual temporal behavior of solution.

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In this article we use a non-classical approach to investigate different physical effects of Cosserat-Maxwell fluid flow with non-Fourier heat transfer mechanism. Furthermore, a new numerical approach is used and outlined for computing and analyzing the behavior of such flows. In particular, continuous Galerkin-Petrov discretization scheme is embedded with shooting method to get the numerical algorithm to solve the stagnation point flow of Cosserat-Maxwell fluid with Cattaneo-Christov heat transfer. The mathematical description of the physical problem is stated in the form of partial differential equations (PDEs) which govern the flow mechanism. Further, the suitable transformations are utilized to describe the governing PDEs into their respective ordinary differential equations. Numerical experiments are performed for a specific case where there are weak concentrations of the flow near the stretching surface thereby allowing the microelement to rotate and generate vortex flow near the stretching surface. Buoyancy effects