•Heat transfer modeling for solidification of NEPCM is presented.•In order to simulation, finite element has been employed.•Highest discharging rate is obtained for platelet.•Length of fins has ...direct relationship with solid fraction.
The current article investigates the impact of using fins and nano sized materials on performance of discharging system. Various shapes for nanoparticle have been considered. Cold fluid flows in both inner and outer layers and middle layer is full of PCM. To make a careful choice of designing heat storage based on uniform solidification, two factor has been examined; length of fins and shape factor. Temperature and solid fraction distributions were reported at various time steps. The homogeneous model for nanofluid has been extended by incorporating various shapes of CuO nanoparticles. The mathematical model has been offered in the form of PDE's, which were solved using Galerkin FEM. It can be observed that the employing nanofluid augments the discharging rate and best performance is obtained for platelet shape.
In current article, transportation of CuO nanoparticles through a porous enclosure is demonstrated. The enclosure has complex shaped hot wall. Porous media has been simulated via two temperature ...equations. Magnetic force impact on nanofluid treatment was considered. Control volume based finite element method has been described to solve current article in vorticity stream function form. Single phase model was chosen for nanofluid. Nanofluid characteristics are predicted via KKL model. Roles of solid-nanofluid interface heat transfer parameter (Nhs), porosity, Hartmann and Rayleigh numbers have been illustrated. Outputs illustrated that conduction mode reduces with augment of Ra. Increasing magnetic forces make nanofluid motion to decrease. Temperature gradient of nanofluid decreases with augment of Nhs. Reducing porosity leads to enhance in Nusselt number.
The aim of this article is to study the combined effects of heat generation and chemical reaction on magnetohydrodynamic (MHD) natural convection flow over a moving plate embedded in a porous medium. ...Natural convection is caused due to buoyancy forced which has been induced because of temperature and concentration gradients. The general condition of velocity has been considered on the plate surface with Newtonian heating and constant wall concentration. The effect of thermal radiation is also considered in the energy equation. The main objective here is to study the relative behavior of the magnetic field. That is the magnetic field shows two types of relative behavior. More exactly, when the magnetic field is fixed relative to the fluid (MFFRF) and the magnetic field is fixed relative to the plate (MFFRP). The general exact solution of the problem is determined by the Laplace transform method. Particular solutions for two special cases namely the plate with variable vibration and the plate with sine and cosine oscillations are also determined. Moreover, the solutions when ζ → ∞ for both cases i.e. MFFRF and MFFRP are also obtained as special cases. The velocity profile is presented in the form of mechanical, thermal and concentration components. Velocity obtained for oscillating plate condition is written in terms of steady-state and transient parts. Exact solutions obtained in this paper are interpreted graphically using computational software Mathcad-15 to examine the effects of various pertinent parameters such as Casson fluid parameter, the permeability of porous medium, chemical reaction parameter, heat generation parameter, buoyancy force parameter, magnetic parameter, and radiation parameter. Results for Sherwood number, skin-friction, and Nusselt number are numerically computed and discussed.
•Nanofluid thermal management inside a porous media is studied.•CVFEM is offered and employed to model the solutions of the developed problem.•Nuave goes up by increasing in Radiation ...parameter.•Conduction becomes more effective as enhancing the Hartmann number.
In this manuscript, we present nanofluid thermal management inside a porous media including magnetic force and radiation heat sources. The systems of PDEs were changed into the non-dimensional form by means of the suitable transform. To gain the outputs, control volume finite element method (CVFEM) was utilized. Radiative source term was involved in final PDEs. Isotherms and streamlines are plotted to demonstrate the variation of Hartmann number, radiation factor, buoyancy and nanoparticles' shape on nanofluid behavior. Outputs demonstrate that convective mode becomes stronger with augment of shape factor. By involving source terms of magnetic field, conduction becomes more effective. Average Nusselt number grows as enhancing the shape effect parameters “m”, Radiation effect and Raleigh number. As increasing Radiation and Raleigh parameters average temperature deceases gradually. The comparative study is also presented, which shows the reliability and efficiency of the CVFEM. Graphical study also shows strengthen of suggested technique.
•Entropy generation of nanomaterial MHD flow is studied.•To obtain the outputs, CVFEM has been employed.•Exergy loss augments with growth of Ha.•Bejan number has inverse relationship with Da and Ra ...make.
An investigation has been conducted to study Lorentz effect on nanomaterial behavior within a permeable space including innovative numerical technique namely CVFEM. Iron oxide has been mixed with H2O and porous domain was filled with this nanomaterial. The impacts of the flow and geometric variables on entropy generation along with the heat transfer have been examined. The simulations have been carried out with wide ranges of the magnetic force, permeability and Rayleigh numbers. The outcomes indicate that the Darcy term has inverse relationship with temperature of hot surface. Stronger convection mode and lower exergy loss appear when buoyancy forces augment. Entropy generation goes up with growth of Hartmann number.
In the present study, a set of experiments were accomplished to appraise the thermal performance and heat transfer of
n
-pentane-acetone and
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-pentane-methanol mixtures inside a gravity-assisted ...thermosyphon heat pipe. Pure
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-pentane, acetone and methanol were also tested as the carrying fluid to produce some reference data. The heat pipe was manufactured from copper with length and diameter of 290 and 20 mm, respectively. The effect of multiple factors covering the input heat to the evaporator section, the filling ratio of the carrying fluid, heat pipe tilt angle and also the type of the carrying fluid on temperature distribution and thermal performance of the heat pipe was investigated. The results demonstrated that the thermo-physical properties of the carrying fluid were the key factor controlling the heat pipe efficiency. The vapour pressure and boiling temperature of the carrying fluid controlled the thermal efficiency of the system such that for
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-pentane-acetone, the highest thermal efficiency was obtained. Also, it was identified that the filling ratio of the system is a key operating factor such that the value of the filling ratio was small for the evaporative carrying fluid (binary mixtures), while it was large for the non-evaporative carrying fluids. Also, heat pipe tilt angle was impressed by the type of the carrying fluid; the optimum tilt angle was 55 degree for the binary mixtures, while it was 65° for the pure liquids.
In the modern era, diathermic oils have been gotten the great attention from researchers due to its notable and momentous applications in engineering, mechanics and in the industrial field. The aim ...of this paper is to model the problem to augment the heat transfer rate of diathermic oils, specifically, Engine-oil (EO) and Kerosene-oil (KO) are taken. The present work is dedicated to examine the shape impacts of molybdenum-disulfide (MoS
) nanoparticles in the free convection magnetohydrodynamic (MHD) flow of Brinkman-type nanofluid in a rotating frame. The problem is modeled in terms of partial differential equations with oscillatory boundary conditions. The integer-order model is transformed to fractional-order model in time (Caputo-Fabrizio). The exact solutions are obtained using the Laplace transform technique. Figures are drawn to compare the different non-spherically shaped molybdenum-disulfide nanoparticles on secondary and primary velocities. The Nusselt number is computed in the tabular form and discussed in detail. It is worth noting that platelet and blade shape of MoS
nanoparticle has more tendency to improve the heat transfer rate of both fluids as compared to nanoparticles with brick and cylinder shapes. It is also shown that the rate of heat transfer enhances 13.51% by adding MoS
in engine oil which improved its lubrication properties.
The significance of solar energy has recently diverted the attention of researchers; this is due to the experimental or the numerical analyises of solar energy and lack of fractional analytic ...approaches. This manuscript is communicated to model the problem of the enhancement of heat transfer rate of solar energy devices, using single and multi-walled carbon nanotubes (SWCNTs and MWCNTs) and to investigate the analytic solutions of the modeled problem. The nano-sized particles are added to the heat transfer fluid such as single and multi-walled carbon nanotubes (SWCNTs and MWCNTs). The governing partial differential equations are modeled by the newly defined Caputo-Fabrizio fractional derivatives. The analytic solutions have been investigated for heat transfer and velocity field by employing Laplace transforms. The heat transfer and profile of nanofluids are presented by the variations of different nanoparticles and their different volume fractions. The similarities and differences between single and multi-walled carbon nanotubes (SWCNTs and MWCNTs) improve the thermo-physical properties of the nanofluid. Theoretical results assure that the efficiency of solar collectors is enhanced by adding single and multi-walled carbon nanotubes (SWCNTs and MWCNTs). Finally, the graphical results indicated that performance of solar collector is significant via Caputo-Fabrizio fractional derivatives and the incoming sunlight can be absorbed more effectively.
The aim of this article is to study time dependent rotating single-wall electrically conducting carbon nanotubes with aqueous suspensions under the influence of nonlinear thermal radiation in a ...permeable medium. The impact of viscous dissipation is taken into account. The basic governing equations, which are in the form of partial differential equations (PDEs), are transformed to a set of ordinary differential equations (ODEs) suitable for transformations. The homotopy analysis method (HAM) is applied for the solution. The effect of numerous parameters on the temperature and velocity fields is explanation by graphs. Furthermore, the action of significant parameters on the mass transportation and the rates of fiction factor are determined and discussed by plots in detail. The boundary layer thickness was reduced by a greater rotation rate parameter in our established simulations. Moreover, velocity and temperature profiles decreased with increases of the unsteadiness parameter. The action of radiation phenomena acts as a source of energy to the fluid system. For a greater rotation parameter value, the thickness of the thermal boundary layer decreases. The unsteadiness parameter rises with velocity and the temperature profile decreases. Higher value of ϕ augments the strength of frictional force within a liquid motion. For greater R and θ w ; the heat transfer rate rises. Temperature profile reduces by rising values of Pr .
This articles deals with unsteady MHD free convection flow of blood with carbon nanotubes. The flow is over an oscillating vertical plate embedded in a porous medium. Both single-wall carbon ...nanotubes (SWCNTs) and multiple-wall carbon nanotubes (MWCNTs) are used with human blood as base fluid. The problem is modelled and then solved for exact solution using the Laplace transform technique. Expressions for velocity and temperature are determined and expressed in terms of complementary error functions. Results are plotted and discussed for embedded parameters. It is observed that velocity decreases with increasing CNTs volume fraction and an increase in CNTs volume fraction increases the blood temperature, which leads to an increase in the heat transfer rates. A validation of the present work is shown by comparing the current results with existing literature. Keywords: Blood flow, Nanofluids, SWCNTs and MWCNTs, Thermal fluid, Exact solution
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