In-house Numerical Code Research Articles

The characterization of cell traction force on nonflat surfaces with different curvature by elastic hydrogel microspheres.

It is of great importance to study the detachment/attachment behaviors of cells (cancer cell, immune cell, and epithelial cell), as they are closely related with tumor metastasis, immunoreaction, and tissue development at variety scales. To characterize the detachment/attachment during the interaction between cells and substrate, some researchers proposed using cell traction force (CTF) as the indicator. To date, various strategies have been developed to measure the CTF. However, these methods only realize the measurements of cell passive forces on flat cases. To quantify the active CTF on nonflat surfaces, which can better mimic the in vivo case, we employed elastic hydrogel microspheres as a force sensor. The microspheres were fabricated by microfluidic chips with controllable size and mechanical properties to mimic substrate. Cells were cultured on microsphere and the CTF led to the deformation of microsphere. By detecting the morphology information, the CTF exerted by attached cells can be calculated by the in-house numerical code. Using these microspheres, the CTF of various cells (including tumor cell, immunological cell, and epithelium cell) were successfully obtained on nonflat surfaces with different curvature radii. The proposed method provides a versatile platform to measure the CTF with high precision and to understand the detachment/attachment behaviors during physiology processes.

An in-house numerical code to assist in designing a small-scale red-hot air furnace

The implementation of a sustainable development concept that involves an improvement of resource use efficiency, whilst maximizing the utilization of locally available biomass resources, has contributed to an increased interest in the combined heat and power systems based on externally fired gas turbines. Since the high-temperature gas/gas heat exchangers intended to heat the turbine inlet air are the key components of such systems, intensified research on exchangers of this type has been observed over the last decade. This work presents the in-house calculation code developed to analyze the heat transfer between the hot-side and cold-side streams in the small-scale red-hot air furnace of a unique design. The performed calculations, based on the assumed thermal and flow operation parameters and technical specifications, allowed to determine the required heat exchange surface area of the furnace to achieve the target outlet conditions. The calculation code allows for determining the geometry of a furnace, including its overall dimensions, number of tubes, and their bent sections in the heat exchange parts. The study of the laboratory-scale furnace performance has demonstrated its good agreement with the simulation results, thereby proving the code a reliable tool in designing.

Hydrogen Jet Flame Control by Global Mode

In this study, we employ the potential of the global instability phenomenon to qualitatively alter the dynamics of a turbulent flame. We adopt the large eddy simulation method and an in-house numerical code. For the combustion process we do not include explicit sub-filter modeling. The accuracy of this ‘no combustion model’ approach is verified by comparison against the Eulerian Stochastic Fields method. We include several test cases representing different flow regimes, including convective and absolutely unstable conditions. The focus is on a counter-current configuration, which includes a central jet nozzle supplying hydrogen fuel surrounded by a somewhat larger co-axial nozzle sucking fluid from the surroundings of the central nozzle. The suction generates a counterflow where global instability is found to be triggered if sufficiently strong suction is applied. The critical suction value IGI\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$I_{GI}$$\\end{document} is larger if the level of the inlet turbulence intensity Ti\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$T_i$$\\end{document} is increased. Depending on the suction strength, the flame quickly stabilizes, either as being attached to the nozzle or as a lifted flame hovering at a height of a few fuel nozzle diameters. Additionally, it is shown that increasing Ti\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$T_i$$\\end{document} can assist an initially lifted flame to attach to the nozzle. Flame lifting is the result of self-induced strong toroidal vortices that lead to leaner combustion conditions of the mixture upstream of the flame base. The toroidal vortices prevent upstream flame propagation and lead to a very intense mixing process that gives rise to the lifted reaction zone. This ensures almost complete fuel combustion at a short distance from the inlet. On the contrary, when the suction strength is below IGI\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$I_{GI}$$\\end{document}, the flames are attached and a high temperature near the fuel inlet causes an increase in molecular viscosity. This tends to laminarize the mixing layer between the fuel and oxidizer. The flames appear as if they were laminar and non-premixed over a long distance from the inlet. In such a situation, a significant amount of fuel remains unburned.

Simulation of Vibrating Intrinsic Reverberation Chambers Using an FDTD Conformal Mesh

This article presents an original simulation procedure devoted to the simulation of arbitrary-shaped reverberation chambers especially well suited for the analysis of vibrating intrinsic reverberation chambers (VIRC). The described method is based upon conformal finite-difference in time-domain (FDTD) modeling in order to model the rough surface geometry of the VIRC walls. On this point, we take full advantage of the performance of our in-house numerical FDTD code called TEMSI-FD and of its associated conformal mesher. First, uncorrelated geometries of the VIRC under study have been generated in order to analyze its performance as a RC from the computed <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$S_{11}$</tex-math></inline-formula> parameter of a log-periodic antenna. Second, correlated geometries have been generated in order to consider the continuous movement of the VIRC walls with a straightforward algorithm, each geometry being associated to a given instant. In both frequency and time domains, numerical outcomes demonstrate excellent agreement with experimental results available in the literature in similar conditions.

Heat transfer by oil natural convection in an annular space under combined effects of carbon nanotubes and electric field

In this study, the combined impact of carbon nanotube volume fractions and the electric field on the enhancement of dielectric oil heat transfer is investigated. The geometry studied is an annular layer filled with the dielectric oil and bounded by two eccentric or concentric cylinders. A temperature gradient and an electrical potential difference are applied between the two cylindrical walls. The goal is to analyse the flow behaviour and the heat transfer improvement using a double enhancement technique by combining an active (electric field) and passive (nanoparticles) approach. An in-house numerical simulation code using the finite volume method was developed to solve the set of coupled equations describing the conservation laws of the electro-thermo-hydrodynamic flow associated with the oil. A parametric study, outlining the influence of different relevant variables has been performed. The parameters investigated are the thermal Rayleigh number (2000 ≤ T ≤ 100 000), the electrical Rayleigh number (100 ≤ T ≤ 600), the radius ratio (0.1 ≤ Γ ≤ 0.9), the eccentricity (0 % ≤ e ≤ 90%), the nanotubes volume fraction (0 % ≤ Φ ≤ 0.5%)and the injection level (1 ≤ C ≤ 10) respectively. The effect of these variables on the heat transfer intensification is examined in detail. According to the adopted configuration, heat transfer intensifications between 3% and 77% have been recorded essentially when an electric field was applied. Also, the addition of a 0.5% volume fraction of carbon nanotubes provides a heat transfer improvement of around 27%. Furthermore, for a first time a multiparameter correlation has been developed. This correlation can be useful to better understand the impact of various physical parameters on the heat transfer in annular spaces and also to predict exact values of the Nusselt number.

NUMERICAL STUDY OF THE INFLUENCE OF TEMPERATURE-DEPENDENT VISCOSITY ON THE UNSTEADY LAMINAR FLOW AND HEAT TRANSFER OF A VISCOUS INCOMPRESSIBLE FLUID DUE TO A ROTATING DISC

In this article, the effect of temperature-dependent viscosity (TVD) on the unsteady laminar flow and heat transfer (HT) of a viscous incompressible fluid due to a rotating disc (RD) has been investigated numerically by exploiting an in-house numerical code. A set of time-dependent, axisymmetric, and non-linear partial differential equations which govern the fluid flows and heat transfer are reduced to non-linear local non-similarity ordinary differential equations by introducing a newly developed group of transformations for different time regimes. Three different solution methods, such as, (i) perturbation solution method for small t, (ii) asymptotic solution method for large t, and (iii) implicit finite difference method for the entire t regime, have been applied to solve the resulting equations treating t as the time-dependent rotating parameter. The local radial skin friction, tangential skin friction and the heat transfer are computed at the surface of the disc for different numerical parameters, such as, Prandtl number, Pr and the viscosity-variation parameter, e. Besides, the key dimensionless quantities such as velocity and temperature profiles, which are inherently linked with the boundary layer thickness, are presented graphically for different values of e while Pr = 0.72. It is found that the dimensionless radial, tangential and axial velocity profiles decrease as e increases, and consequently, the momentum boundary layer thickness is decreased. On the other hand, the non-dimensional temperature profiles are increased owing to the increasing values of e, and this effect eventually leads to a small increment in the thermal boundary layer thickness.

Experimental and Numerical Assessments of the Effects of Vacuum and Solar Film on the Performance of a Low Concentration Eccentric Solar Collector

Abstract Low concentration collectors are usually recommended for water heating and refrigeration systems. The literature reveals lack of information on numerical modeling, experimental data, and thermal performance of eccentric evacuated double tube solar collectors. This study is focused on eccentric solar collectors since this arrangement allows adequate concentration for achieving relatively high temperatures while having small size and occupying less space. The effects of the vacuum in the annular space and reflective film on the enhancement of working fluid heating and overall thermal performance were also assessed. An in-house numerical code using the finite volume method was used to discretize the conservation equations and the predictions were validated by experimental results obtained from an experimental rig that was constructed and instrumented for outdoor tests. The experiments were performed in the city of Campinas-Brazil during the autumn season. The investigated versions of the eccentric double tube solar collector include a version with a reflective film and vacuum, a second version with a reflective film but without vacuum, a third arrangement without a reflective film but with vacuum, and finally a version without both a reflective film and vacuum. The results showed that the version with reflective film and vacuum demonstrated high efficiency achieving 89%. The lowest efficiency of 42% was achieved by the version without both reflective film and vacuum. The comparative analysis of the four versions shows that the incorporation of reflective film increases the collector efficiency by 28%, while the vacuum increases the efficiency by about 1.3%.

Analysis of the Shear-Thinning Viscosity Behavior of the Johnson–Segalman Viscoelastic Fluids

This paper presents a numerical comparison of viscoelastic shear-thinning fluid flow using a generalized Oldroyd-B model and Johnson–Segalman model under various settings. Results for the standard shear-thinning generalization of Oldroyd-B model are used as a reference for comparison with those obtained for the same flow cases using Johnson–Segalman model that has specific adjustment of convected derivative to assure shear-thinning behavior. The modeling strategy is first briefly described, pointing out the main differences between the generalized Oldroyd-B model (using the Cross model for shear-thinning viscosity) and the Johnson–Segalman model operating in shear-thinning regime. Then, both models are used for blood flow simulation in an idealized stenosed axisymmetric vessel under different flow rates for various model parameters. The simulations are performed using an in-house numerical code based on finite-volume discretization. The obtained results are mutually compared and discussed in detail, focusing on the qualitative assessment of the most distinct flow field differences. It is shown that despite all models sharing the same asymptotic viscosities, the behavior of the Johnson–Segalman model can be (depending on flow regime) quite different from the predictions of the generalized Oldroyd-B model.

A novel method for the determination of frictional resistance coefficient for a plate with inhomogeneous roughness

Ship performance is largely influenced by roughness on immersed surfaces, which is mostly inhomogeneous. Therefore, the prediction of the effects of roughness on ship performance is of crucial importance. Even though it has several drawbacks, the Granville similarity law scaling method is widely reported in the literature for predicting the frictional resistance coefficient of a rough surface. Lately, the CFD approach based on a modified wall function approach has also been used, since it allows for a more comprehensive analysis of the effects of roughness. In this paper, a novel method for assessing the frictional resistance coefficient for rough surfaces is proposed. The proposed method can take into account the non-uniform distribution of friction velocity, as well as the roughness Reynolds number, and thus the non-uniform distribution of roughness function values can be predicted along a rough surface. Additionally, the proposed method can consider the non-uniform distribution of roughness and its effect on the frictional coefficient of a flat plate. Based on the proposed method, an in-house numerical code is developed, allowing for the rapid and accurate assessment of the frictional resistance coefficient for a rough surface. The applicability of the proposed method is demonstrated by comparison with the CFD approach for several surface conditions defined with different roughness function models and the longitudinal position of roughness. A comparison is made of two flat plates representing one containership and one tanker at two different speeds. The obtained relative deviations in the predicted frictional resistance coefficients for all surface conditions are lower than 2.5%. Therefore, it is demonstrated that the proposed method can be used for estimating the frictional resistance coefficient of various surface conditions defined with roughness function models and the longitudinal positions of roughness.

Hybrid Simulation of Turbulent Natural Convection in an Enclosure with Thermally-Conductive Walls

This paper analyzes the interaction of high Rayleigh number flow with conjugate heat transfer. The two-relaxation time lattice Boltzmann is used as a turbulent buoyancy-driven flow solver whereas the implicit finite difference technique is applied as a heat transfer solver. An in-house numerical code is developed and successfully validated on typical CFD problems. The impact of the Biot number, heat diffusivity ratio and the Rayleigh number on turbulent fluid flow and heat transfer patterns is studied. It is revealed that the thermally-conductive walls of finite thickness reduce the heat transfer rate. The temperature of the cooled wall slightly depends on the value of the buoyancy force. The heat diffusivity ratio has a significant effect on thermal and flow behavior. The Biot number significantly affects the mean Nusselt number at the right solid–fluid interface whereas the mean Nusselt number at the left interface is almost insensible to the Biot number variation.

Numerical Simulation of Water Entry of Wedges in Waves Using A CIP-Based Model

In this study, the water entry of wedges in regular waves is numerically investigated by a two-dimensional in-house numerical code. The numerical model based on the viscous Navier-Stokes (N-S) equations employs a high-order different method—the constrained interpolation profile (CIP) method to discretize the convection term. A Volume of Fluid (VOF)-type method, the tangent of hyperbola for interface capturing/slope weighting (THINC/SW) is employed to capture the free surface/interface, and an immersed boundary method is adopted to treat the motion of wedges. The momentum source function derived from the Boussinesq equation is applied as an internal wavemaker to generate regular waves. The accuracy of the numerical model is validated in comparison with experimental results in the literature. The results of water entry in waves are provided in terms of the impact force of wedge, velocity and pressure distributions of fluid. Considerable attention is paid to the effects of wave parameters and the position of wedge impacting the water surface. It is found that the existence of waves significantly influences the velocity and pressure field of fluid and impact force on the wedges.

Modelling thermal behaviour of a single solid particle pyrolysing in a hot gas flow

Pyrolysis is a first stage of the solid fuel combustion. Due to complexity of the phenomena during heating and the fuels’ variety, the analysis of their conversion and its modelling is still of importance from the cognitive and the practical point of view. In the paper the original mathematical 1D model to describe the behaviour of heated fuel particle is presented. The model accounts for the water phase transition (evaporation and condensation), and the transport of released gas and liquid products inside the particle. An in-house numerical code in FORTRAN was developed. The proposed new approach describing the devolatilization source term includes the limit pyrolysis progress function. It takes into account the proper direction of particle structure changes due to decomposition. A strong emphasis was placed on the role of transport processes of products inside the porous grain and their impact on the devolatilization time. Thus, the characteristic plateau in a temperature distribution at the level of 100oC can be predicted. The times complete conversion of the single solid particle depending on the fuel type and size were analysed and discussed. Based on the calculation results, the main differences in behaviour of heated particle between biomass and coal were outlined.

Numerical Simulation for Rock Fracture Viscoelastic Creep under Dry Conditions

In many rock engineering projects such as hydrocarbon extraction and geothermal energy utilization, the hydraulic and mechanical behavior of rock fractures significantly affects the safety and profitability of the project. In field conditions, the hydraulic and mechanical behavior of rock fractures changes with time (the rock fractures creep), and this creep is not negligible even under dry conditions. In addition, creep is strongly affected by the rock fracture surface geometry. However, there is not much literature systematically studying the effect of surface geometry on rock fracture creep under dry conditions. This paper presents the results of a numerical study considering the effect of surface geometry on rough fracture viscoelastic deformations. An in-house numerical code has been developed to simulate the viscoelastic deformation of rough fractures. In addition, another numerical code has been developed to generate synthetic rough fracture surfaces by systematically changing the surface roughness parameters: the Hurst exponent, mismatch length, and root mean square roughness. The results indicate that by increasing the Hurst exponent or decreasing the mismatch length or decreasing the root mean square roughness, the fracture mean aperture decreases, and the contact ratio (number of contacting cells/total number of cells) increases faster with time.

Dynamics of viscoelastic fluid in a rotating soft microchannel

In this study, we numerically investigate the effects of rotational forces, viz., centrifugal force and Coriolis force, on the flow dynamics of a viscoelastic fluid in a polymeric layer grafted microchannel. The viscoelastic fluid is represented by the Oldroyd-B model, and the effect of viscoelasticity on the underlying transport is studied. A numerical procedure consistent with the finite difference method is used to solve the system of partial differential equations. The numerical model takes into consideration, among many others, the drag effects of the “soft layer” and the transiences in the flow dynamics leading to the steady state. The complex interplay between the effect of rotational forcing and the presence of the soft layer is observed to lead to vital conclusions that could improve the design of many lab-on-a-compact disc based microfluidic devices. In addition, the effect of elasticity on the flow dynamics in the presence of rotational forces and soft layer induced drag force is studied. The in-house numerical code employs the finite difference numerical scheme to discretize the equations and consequently solves the obtained system of linear algebraic equations using the Gauss–Seidel iterative scheme. By demonstrating the velocity profiles, we discuss the effect of the various rheological parameters on the underlying transport feature. Finally, the effect of the rotation on the net throughput is studied extensively.

Influence of the free surface on hydrodynamics in a bubble column

In this paper, the influence of the free surface on hydrodynamics is investigated numerically for a pilot-scale bubble column. The free surface is modelled by means of the Volume of Fluid method (VOF), whereas the gas entities are represented by means of the Direct Simulation Monte Carlo (DSMC) method. The VOF method is parallelized using MPI and incorporated in already parallel in-house numerical code for DSMC, FoxBerry. The results obtained with the modeled free surface are compared with the reference simulation, in which the free surface is mimicked using the outlet slits, placed at the top of the column. The results show a significant impact of the free surface on generation of the small-scale eddies. Moreover, the presence of the free surface reduces the gas-holdup in the domain.

A Numerical Prediction on the Transient Response of a Spar-Type Floating Offshore Wind Turbine in Freak Waves

Abstract Simulations are conducted in time domain to investigate the dynamic response of a spar-type floating offshore wind turbine (FOWT) under the freak wave scenarios. Toward this end, a coupled aero-hydro-mooring in-house numerical code is adopted to perform the simulations. The methodology includes a blade-element-momentum (BEM) model for simulating the aerodynamic loads, a nonlinear model for simulating the hydrodynamic loads, a nonlinear restoring model of Spar buoy, and a nonlinear algorithm for simulating the mooring cables. The OC3 Hywind spar-type FOWT is adopted as an example to study the dynamic response under the freak wave conditions, meanwhile the time series of freak waves are generated using the random frequency components selection phase modulation method. The motion of platform, the tension applied on the mooring lines, and the power generation performance are documented in several cases. According to the simulations, it is indicated that when a freak wave acts on the FOWT, the transient motion of the FOWT is induced in all degrees-of-freedom, as well as the produced power decreases rapidly. Furthermore, the impact of freak wave parameters on the motion of FOWT is discussed.

Rotating electroosmotic flow of power-law fluid through polyelectrolyte grafted microchannel

Due to evergrowing importance of understanding flow of bio-fluids in Lab-on-CD based systems, we investigate the flow behaviour of power-law fluids in the rotating electroosmotic flow through a polyelectrolyte grafted (soft) narrow channel. We use an in-house numerical code to solve the governing transport equations for the velocities and flow rates in a rotating channel subjected to an applied external electric field. We show the strong effect of polyelectrolyte layer on the flow behaviour and find an increase in flow rate as we increase the size of the polyelectrolyte layer. We also show that rheology strongly influences the interplay of the Coriolis forces due to rotation and electrical body force due to the applied electric field. We show that the velocities are generally higher for shear thinning fluids as compared to shear thickening fluids. We also show that presence of polymer brushes in the polyelectrolyte layer creates a drag on the fluid which reduces velocities. We also show that the flow rates are strongly altered by the effect of rotation and that shear thickening fluids have lower flow rates than shear thinning fluids. The effect of fluid rheology on the shear stress distribution is also discussed. We believe that studying effect of fluid rheology becomes very important for designing soft channel based Lab-on-CD systems driven by electroosmotic forcing and dealing with rheologically complex bio-fluids such as blood, saliva or mucus.

Assessing the thermal performance of a rooftop solar chimney attached to a single room

The passive design approach can help to maintain comfortable thermal conditions in buildings and reduce energy consumption by minimizing the use of auxiliary mechanical or electromechanical air-conditioning systems. In particular, the implementation of solar chimneys for cooling increases energy efficiency in buildings located in warm climates by decreasing electricity bills and CO2 emissions. This paper presents a pseudo-transient thermal performance assessment of a ventilated room with and without the integration of a rooftop solar chimney for summer and winter conditions in Mérida (México). A global in-house numerical code based on a novel integration of both computational fluid dynamics and global energy balances was developed to solve the conjugate turbulent heat transfer in the ventilated room with the integrated solar chimney system. Numerical results were verified and validated, and they showed a good agreement with the benchmark solutions reported in the literature. The room with the integrated solar chimney improved the ventilation rates by 8–45% in summer and by 1.16–24.89% in winter. Both configurations under analysis fulfilled the requirements of 0.5–2.5 air changes per hour by the ASHRAE Standard 62.1. In general, we concluded that the integration of the solar chimney system showed higher ventilation rates, demonstrating its higher potential as a passive ventilation system in warm climates.

Impact of Evaporation Models and Droplet Size on Auto-ignition and Lift-off Height in a Spray Jet Flame

ABSTRACT In the current work, the jet spray flame reflecting an experimental configuration of a piloted spray burner with a vitiated hot co-flow is modeled using large eddy simulation (LES). We consider a diluted polydisperse spray, which evaporates and diffuses from a fuel-rich spray core, mixes with an oxidizer and eventually auto-ignites. The objective of the present study is to assess an influence of evaporation models and mean droplet diameter on the combustion process in a lifted flame, starting from an auto-ignition up to the flame stabilization. Three evaporation models are involved, i.e., (i) “D2 law”, (ii) infinite conductivity model with Stefan flow effect, and (iii) infinite conductivity non-equilibrium evaporation model based on a Langmuir-Knudsen law. An in-house high-order numerical code was used to carry out the computations. The continuous gas phase is modeled in the Eulerian coordinate system while the spray droplets are tracked in space in the Lagrangian manner. The obtained results show that in a stable combustion regime a flame size and liftoff height only slightly depend on evaporation model. However, in general, it is observed that the spray size can affect the flame structure to a much larger extent. On the other hand, for bigger droplets differences in initial size distribution cause only small flame movement downstream or upstream toward the fuel nozzle. For auto-ignition and initial flame development phase it is observed that both the droplets size and evaporation model affect the obtained results significantly.

Thermal performance augmentation of metal foam infused phase change material using a partial filling strategy: An evaluation for fill height ratio and porosity

Infusion of a metal foam in a phase change material (PCM) used for a latent heat thermal energy storage (LHTES) system significantly improves the melting performance. The presence of metal foam in PCM, however, suppresses the natural convective transport, increases the cost, and depletes the TES capacity. An optimum thermal conductivity enhancer (TCE) density strategy is developed in the present study to determine the effective metal foam distribution and concentration. The primary objective of the strategy is the local installation of the metal foam mass at the high-temperature gradients region (high thermal potential) and elimination of the same at the region of low-temperature gradients (lower thermal potential) for the efficient use of the metal foam. Thus, the melting performance of the various fill height ratios (i.e. 0.25H, 0.5H, and 0.75H) and the metal foam porosities (0.97, 0.95, 0.92, and 0.90) are studied and comprehensively compared. To accomplish this, an in-house numerical code is developed using an enthalpy porosity approach supplemented with the local thermal non-equilibrium (LTNE) technique. Results show that the incorporation of the metal foam-PCM composite (MFPC) only at the lower portion of the enclosure enhances the total thermal transport. Further, the metal foam with the full height (H) and 0.75H require nearly the same total melting time and show that the total melting time increases as the fill height ratio further decreases. The influence of varying the porosities with the fixed fill height ratio of metal foam shows that if the porosity decreases, the total melting time decreases with a penalty of less TES capacity. By means of economic assessment, it is recommended that if the economy and TES capacity are major concerns of the thermal performance, a high porosity metal foam should be chosen with a compromise on the total melting time. Similarly, the LHTES systems targeting the higher melting rate can be designed with a low porosity metal foam, which increases the cost and reduces the TES capacity.