Increasing Lewis Number Research Articles

Numerical exploration of micropolar fluid stratified flow over curved stretching sheet under buoyancy effect

AbstractThis article focuses on the effect of buoyancy on the bioconvective micropolar fluid flow over a curved stretching surface under the slip boundary condition. Mass and heat transfer analysis has been analysed using double stratification, linear heat source, chemical reaction and Joule dissipation. The calculation of entropy formation in a fluid flow is also illustrated. Using similarity transformations, the system of partial differential equations is transformed into a set of ordinary differential equations through reduction in the flow equations and then solved using the numerical methodology of the Runge‐Kutta‐Fehlberg 4th‐5th order method. The mathematical data obtained for velocity, temperature, concentration, and bio‐convection profiles with different parameters are presented on graphs. The velocity profile exhibits consistent behaviour near the buoyancy parameter, with a decrease at the boundary followed by an increase. Notably, the velocity profile experiences a decrease under first‐order slip conditions but grows when subjected to second‐order slip. Micro‐rotation intensifies as the material parameter increases. Conversely, temperature and concentration has declined as the stratification parameter rises. Additionally, the concentration of motile microorganisms reduces with increasing Lewis number and Peclet number. As the material parameter rises, entropy decreases while the Bejan number increases.

Computational workflow to monitor the electroosmosis of nanofluidic flow in the vicinity of a bounding surface

This investigation studies the flow of a boundary layer with electroosmotic forces on a nanofluid with gyrotactic microorganisms along the vertical Riga plate. This sort of fluid movement necessitates specific mathematical techniques and numerical simulations. In addition, the boundary-layer flow is induced by the mass and heat transfer, Joule heating, and viscous dissipation. A mathematical model is simulated by non-linear partial differential equations (PDEs). The combination of PDEs is turned into a set of non-linear ordinary differential equations using proper transformations. Some analysis tools are used to investigate the morphological characteristics of the problem while applying suitable boundary conditions. The influence of parameters on the derived solutions is numerically and visually explained through sets of figures. It is elucidated that the concentration of the microorganisms reduces due to an increase in Lewis number which leads to a decrease in the motile microorganism’s density profile. It is seen that the temperature distribution is improved when the chemical reaction and Casson parameter increase. In addition, we find that the application of electro-osmotic forces applied to the surfaces helps to dewater and separate microorganisms from incompressible solid and liquid mixtures.

Impact of micro-rotation on a double-diffusive radiative flow within a lid-driven enclosure fearuring Joule heating, porosity and Lorentz forces

The present paper explores the fluid dynamics, heat and mass transmission characteristics within hexagonal enclosure with square object. The phenomenon encompasses the interplay of various physical mechanism, including micro-rotation of fluid particles, Joule heating, thermal radiation, porous materials, and magnetic field. The governing nonlinear partial differential equations are transformed into non-dimensional form and then investigated numerically using continuous Galerkin finite element method. The pressure component of the momentum equation is removed by employing the Penalty parameter. In order to achieve the consistent solution the value of Penalty parameter is set to 107. The analysis includes several physical parameters, such as Buoyancy ratio (−1–1), micropolar parameter (2–6), Joule heating parameter (0–5), Richardson number (0.5–5), thermal radiation parameter (0.1 – 0.5), Lewis number (0.1–5), Darcy number (0.001–0.1) and Hartmann number (0–50). Results reveal notable trends regarding the impact of key parameters on flow behavior and thermal-solutal transfer within cavity. Increasing Darcy numbers intensify fluid motion and subsequently augments thermal and solutal transfer. The flow regime shifts from shear fricition-dominated at low Richardson number to buoyancy-induced at high Richardson numbers. For concentration-dominant counter flow, a uniform distribution pattern emerges, while aiding flow leads to increased fluid velocity, temperature, and concentration. Additionally, the micropolar parameter influences flow velocity, with varying effects on heat and mass transfer rates depending on the Hartmann number. Mass distribution expands with increasing Lewis number, while temperature rises significantly due to variations in radiation and Joule heating parameters. These findings contribute to a deeper understanding of enclosed flow dynamics and have implications for the optimization of diverse engineering systems.

Double diffusive mixed convective flow over a wedge and cone in the presence of Brownian diffusion and thermophoresis parameter

The present article examines the double diffusion mixed convective nanofluid flow over a wedge and cone in which slip effects as Brownian motion and the thermophoretic parameter are considered. Mixed convective flow over wedges and cones is applied in different technical fields such as fiber technology, nuclear cooling systems, surface treatment, spray deposition techniques, and polymer production. Double diffusion is increasingly significant in scientific fields like astronomy, geosciences, oceanography, and chemical processes. Mixed convection occurs in several applications such as electric devices, solar panels, nuclear power plants, heat exchangers, radiators, and atmospheric boundary layer fluxes. The governing equations of the study are highly coupled nonlinear partial differential equations with surface constraints. The process of similarity transformation used to converts partial differential equations into nondimensional ordinary differential equations, which can be resolved using the MATLAB Bvp5c function. The graphical representation and detailed analysis of variations in velocity, temperature, and concentration distributions of nanofluids are presented. As the mixed convection parameter increases, the fluid’s velocity rises, with a more pronounced effect observed in the cone compared to the wedge. As the Brownian diffusion parameter grows, the fluid temperature increases, and velocity is more pronounced in the wedge scenario compared to the cone. Moreover, an increase in the thermophoresis parameter results in an elevation in the fluid’s temperature. Additionally, the wedge has a higher concentration of fluid and nanoparticles compared to the wedge. Fluid concentration falls with increasing Schmidt number, but fluid nanoparticle concentration decreases with increasing Lewis number.

Effects of magnetic field, fluid properties, and geometric parameters on double-diffusive convection of liquid metals

<sec>Thermal convection in conducting fluids under the influence of a magnetic field is a hot research topic. In this study, a high-precision and high-resolution numerical method is used to directly simulate the double-diffusive convection of liquid metal in a two-dimensional cavity. The study covers the effects of magnetic field strength (<i>Ha</i>), Prandtl number (<i>Pr</i>), Lewis number (<i>Le</i>), and aspect ratio on the dynamics of flow and heat/mass transfer under both horizontal magnetic field and vertical magnetic field. The study considers magnetic field intensities ranging from 0 to 100, Prandtl numbers from 0.01 to 1, Lewis numbers varying from 1 to 100, and aspect ratios spanning from 1 to 12. Within these specified parameter ranges, the outcomes under conditions of no magnetic field (<i>Ha</i> = 0), weak magnetic field (<i>Ha</i> = 10), and strong magnetic field (<i>Ha</i> = 50) are compared with each other.</sec><sec>The results show that the magnetic field primarily suppresses flow, heat transfer, and mass transfer. Under the same strength of the magnetic field, the horizontal magnetic field has a greater suppressing effect than the vertical magnetic field. However, the cases of weak magnetic field and strong magnetic field, their effects on heat and mass transfer are similar. Regardless of the orientation and strength of the magnetic field, the heat transfer efficiency and mass transfer efficiency always increase with Prandtl number increasing. The application of a magnetic field can reduce the increase in heat and mass transfer, and when the magnetic field strength reaches a certain level, the Lorentz force predominates, making the influence of the Prandtl number on heat and mass transfer very small. In the presence of a magnetic field, a bifurcation phenomenon is observed around <i>Pr</i> = 0.9.</sec><sec>Additionally, as the Lewis number increases, the flow transforms from steady flow to periodic flow, and the influence on mass transfer efficiency becomes more significant. For example, under a horizontal magnetic field, the mass transfer efficiency at the maximum Lewis number is about six times that at the minimum Lewis number. Similarly, under a weak vertical magnetic field, the mass transfer efficiency is about nine times higher. The influence of Lewis number on heat transfer efficiency is relatively minor.</sec><sec>Within the range of considered aspect ratios, the heat transfer efficiency and mass transfer efficiency exhibit oscillatory behavior under no magnetic field and weak magnetic field as the aspect ratio increases. However, the heat transfer efficiency and mass transfer efficiency under a strong magnetic field are less affected by the aspect ratio. For flows with the same number of vortices, lower aspect ratio can lead to stronger heat and mass transfer.</sec>

Numerical analysis of heat and mass transfer of MHD natural convection flow in a cavity with effects of source and sink

The study of fluid flow and heat transport is found in many engineering applications such as boilers, nuclear plants, thermal energy storage, and underground pipelines. This study focuses on investigating the effects of isothermal source and sink on natural convection and entropy generation for Casson fluids using the finite element method. Under these considerations, fins ensure the effectiveness of heat transfer systems and flow patterns. Results describe that a higher Ra value leads to promote heat and mass transfer while Ha has the opposite impact. By increasing Ha value, results to retard convective heat transfer. As the Lewis number increases, so does the entropy due to deformation and the Bejan number. The shape optimization study about fins is performed in detail. The aspect ratio of cold fins is varied from 1.25 to 7, found that length and width are nearly directly related to entropy, mass, and heat transfer rates. The correlation coefficient for mean Nusselt and Sherwood number versus sink width is 0.9942, very close to 1, showing a very close direct relationship. The linear regression coefficients for mean Nusselt, Sherwood number and total entropy versus sink lengths are (0.7484, 2.2343), (0.7706, 2.254) and (2.4927, 5.8662), respectively.

Influence of variable viscosity and gravity fluctuation on double diffusive convection in a fluid layer with boundary slab of finite conductivity

The linear stability analysis is carried out for the onset of double-diffusive convection in a fluid layer with a boundary slab along with temperature-dependent viscosity and gravity fluctuation. The authors proposed three types of gravity fluctuation. We considered three cases of gravity field fluctuation: (a) linear and (b)parabolic and (c) cubic. An analytical solution for the subsequent problem is acquired through the perturbation technique. The findings demonstrate that the viscosity variation parameter, the thermal conductivity ratio, the gravity parameter, the depth ratio, and the soret parameter accelerate the start of convection, while the increasing Lewis number slow down the convective motion. Additionally, the system was found to be more stable for the linear type of gravity field fluctuation and more unstable for the cubic type of gravity field fluctuation.

Magnetohydrodynamic double-diffusive mixed convection in a curvilinear cavity filled with nanofluid and containing conducting fins

This work numerically analyzes the mixed convective double diffusion of Fe3O4-water-based nanofluid in a tilt curvilinear lid-driven cavity studied under the effect of an inclined magnetic field. The horizontal upper wall is at a lower thermal and concentration gradient and moves toward the right. The side vertical walls and bottom walls kept adiabatic. Furthermore, two numbers of conducting fins are affixed to the inclined walls at high temperatures and concentrations. The finite element approach is implemented to analyze the considered variables: Richardson number (Ri), Hartmann number (Ha), Reynolds number (Re), Lewis number (Le), buoyancy ratio (N), magnetic inclination angle (α), nanofluid volume fraction (ϕ) as well as the fins length on the heat and mass transport phenomena. The results showed that the Nuavg and Shavg increase by increasing Reynolds number, the nanoparticles volume concentration, and the fin length, while they decrease by increasing Hartmann number. When Ri is small, Nuavg rises with the increasing magnetic field inclination, but when Ri is high, the inclination angle works adversely. On the other hand, the Shavg increases with the rise of the magnetic field inclination for all Ri values. It can be seen also, when Lewis number increases, the Nuavg and Shavg values increase with increasing Ri and magnetic inclination angles.

The Cheng-Minkowycz problem for quadratic convective and radiative heat transfer in a nanofluid saturated porous medium: A revised model

The characteristics of heat transport in a porous medium saturated by a nanoliquid subject to non-linear variations of density-temperature relation and a novel quadratic thermal radiation are studied. For the first time, the well-known Cheng-Minkowycz problem was revisited by nonlinear convection and radiation. The governing equations, based on Darcy's law and Buongiorno's model, are simplified using boundary layer theory, which is further solved by the finite element method. The parameterization of the problem is used to describe the characteristics of the Boussinesq quadratic approximation, Brownian diffusion, quadratic radiation, thermophoretic diffusion, and no-mass flux conditions on the rheological and heat transport features. Our results demonstrate that the rate of heat transport (Nusselt number) is reduced due to thermophoretic diffusion, and the rate of reduction increases with increasing Lewis number values. The Nusselt number is improved due to increasing the values of the Brownian motion parameter at the rate of 0.00616835 and 0.00113362 for the cases of linear thermal radiation and quadratic thermal radiation, respectively. The improvement/reduction rate of the Nusselt number is higher for the case of quadratic thermal convection than for linear thermal convection. Furthermore, the heat transfer rate is achieved for the convection parameter, temperature ratio, and radiation parameter.

Nonsimilar modeling and numerical convective transport analysis of forced flow of radiative Carreau nanofluid with zero mass flux boundary condition

AbstractPresent research focuses on nonsimilar analysis of the flow of a non‐Newtonian Carreau nanofluid against different geometrical configurations affected by thermal radiations. The flow is induced by stretchable surface with the implementation of zero‐net mass‐flux conditions on the surface. This considered model is commonly known as Kuznetsov and Nield's proposed updated model for nanoparticles. The derived flow equations are first nondimensionalized by employing appropriate nonsimilar transformations. The transformed system is analytically tackled by employing the local nonsimilarity (LNS) approach up to the second‐truncation level in association with the numerical algorithm bvp4c. The consequences of appropriate parameters, such as the suction parameter, wedge angle parameter, Weissenberg number, Prandtl number, constant velocity parameter, temperature ratio, Brownian motion, Lewis number, thermophoresis and radiation parameters, on fluid velocity, thermal, and concentration profiles are calculated and graphed. Drag coefficient, Nusselt, and Sherwood numbers are also computed and presented in tabular form. It is observed that intensification in the suction parameter shows augmentation in the local skin friction coefficient. Enhancement in the wedge angle parameter increases both the Sherwood and Nusselt numbers. Enhancement in velocity profile of the nanofluids is noticed with the increasing estimations of suction parameter. Thermophoresis parameter enhances both thermal and concentration profiles, however increasing Lewis number leads to a decline in the concentration boundary layer. With judgment, a comparative assessment is made of the present and previous results. This research may be helpful for the researchers that are interested in studying prospective industrial and engineering nanofluid applications, notably in geophysical and geothermal systems, heat exchangers, solar water heaters, and many others.

Dynamics of Triple Diffusive Free Convective MHD Fluid Flow: Lie Group Transformation

This analysis is interested in the dynamic flow of incompressible triple diffusive fluid flowing through a linear stretched surface. The current study simulates when Boussinesq approximation and MHD are significant. As for originality, a comparative study of all the results for opposing and assisting flow cases is provided. Lie-group transformation is utilized to determine symmetry depletions of partial differential equations. The transformed system of ordinary differential equations is solved using the Runge-Kutta shooting technique. The impacts of magnetic parameter, buoyancy ratio parameter of temperature and concentration, and Lewis number on velocity, temperature, and concentration are depicted through graphs. We observed that the magnetic field parameter decelerates in velocity distribution for both fluid flow cases. Additionally, the same phenomenon was noticed with the buoyancy ratio parameters on both salt concentration distributions. Finally, the influence of heat and mass transfer rates decreases for both fluid flow cases with an increase in Lewis number.

Numerical investigation of 2D double-diffusive convection in rectangular cavities with different aspect ratios: Heat and mass transfer and flow characteristics

In this paper, the dynamical behavior of two-dimensional double-diffusive convection is numerically investigated using a high-accuracy numerical method. The process of flow transition in the presence of buoyancy is studied in detail, and the effects of the fluid properties and geometric parameters on the flow characteristics and heat and mass transfer are discussed. The results show that, as the buoyancy ratio increases from 0 to 2, the flow undergoes a complex series of transitions, from a steady, temperature-dominated state to periodic motion, then chaotic motion, back to periodic motion, and finally back to a steady, concentration-dominated state. At a fixed buoyancy ratio, when the Prandtl number Pr is less than 1, the flow changes from periodic or chaotic to steady with increasing Pr, and the heat and mass transfer efficiencies oscillate with an increasing trend. When Pr≥1, the flow is steady, and the heat and mass transfer remain nearly constant. For low Rayleigh numbers, the heat and mass transfer efficiencies increase monotonically with increasing Lewis number, but the flow is always in a steady state. For high Rayleigh numbers, the flow transitions from steady to periodic or chaotic via a supercritical Hopf bifurcation with increasing Lewis number, and the heat and mass transfer efficiencies oscillate with an increasing trend. In the range of aspect ratios considered in this study, the heat and mass transfer efficiencies exhibit an overall decay with increasing aspect ratio.

Cattaneo-Christov heat and mass flux effect on upper-convected Maxwell nanofluid with gyrotactic motile microorganisms over a porous sheet

The bioconvection nanofluid flow study is one of the most popular topics since it has a wide variety of physical significance in biofuels, bioengineering, and medicinal research. The current study aims to investigate the features of two-dimensional UCM fluid (upper-convected Maxwell nanofluid) flow with Cattaneo-Christov heat and mass flux, motile microorganisms, and bioconvection across a porous sheet. The model incorporates Brownian motion and thermophoresis effects, as well as thermal radiation and activation energy. A proper similarity transformation transforms the governing system of partial differential equations into acceptable ODEs. We used the built-in numerical approach bvp4c in the commercial program MATLAB for the mathematical integration of the generated non-linear issue. The behavior of important physical factors is visually examined. The importance of engineering factors such as local Nusselt number, local Sherwood number, and local density number of microorganisms is also revealed. The stretching parameter increased the velocity field, but the magnetic parameter had the reverse effect. The velocity field is decreased for the increasing values of slip parameter and power-law index. The thermal field is increased for the higher variations of Biot number and temperature ratio parameter. Furthermore, species' thermal and solutal fields are lowered for more significant fluctuations in thermal and solutal relaxation parameters. The microbiological field is reduced when the bioconvection Lewis number increases.

Radiative heat energy exploration on Casson-type nanoliquid induced by a convectively heated porous plate in conjunction with thermophoresis and Brownian movements

The interest of this study is to establish a mathematical model and rheological aspects of chemically reacting Casson-type nanofluid flow considering ethylene glycol-based nanoparticles with thermophoretic diffusion and Brownian motion. The basic flow equations are transmuted into non-dimensional form, these dimensionless leading equations are determined to the most excellent potential systematic using some influential similarity transformations with the employment of the Chebyshev Spectral Collocation method. The outcomes for flow rate, temperature, concentration and engineering quantities distribution are shown in terms of graphical presentation. Findings revealed that larger values of Casson fluid parameter lead to suppress velocity as well as fluid temperature. The nanofluid temperature reduces for Brownian motion parameter and enchances for thermophoresis parameter. An increase in Lewis number means a decrease in mass diffusivity resulted in to suppression in fluid concentration. The model results confirmation is tabulated, and the data assessment of the present study with formerly communicated is found excellently accurate.

A novel spectral relaxation approach for nanofluid flow past a stretching surface in presence of magnetic field and nonlinear radiation

The goal of current research is to peruse the influences of magnetic field and nonlinear radiation on stagnation-point flow of nanofluid past a stretching surface. The Joule heating and viscous dissipation properties are considered for analysis in present work. The spectral relaxation numerical approach is implemented to solve the principal equations of the problem. Also, the influences of nanoparticles thermophoretic diffusion and Brownian motion, as well as Prandtl, Eckert, Lewis, and Biot numbers are analyzed and discussed in details. As a main result, it can be concluded that by increasing Prandtl number the temperature profile reduces for different values of radiation parameter. Furthermore, the results show that the nanofluid temperature profile rises with increase of Lewis number. In addition, the findings reveal that increasing the strength of the magnetic field affects the temperature and concentration of nanofluid.

Analytically investigating of heat transfer parameters with presence of graphene oxide nanoparticles in Williamson-magnetic fluid by AGM and HPM methods

Increasing heat transfer in the field of thermal management is one of the important features of engineering studies. In many cases, the use of nanoparticles leads to increased heat transfer. Hence in this analysis, Graphene Oxide nanoparticles has been used in the field of Magneto hydro Dynamics as a factor to increase heat transfer. The main objectives of this analytical work is to increase the heat transfer of convective currents on a Williamson non-Newtonian rotating cone with graphene oxide nanoparticles. In this paper, we have converted the governing equations in the PDE form have been converted to the ideal ODE form. From the obtained results, it can be seen that increasing the volume fraction of graphene oxide nanoparticles from 0.01 to 0.04 shows favorable thermal effects. An increase in the Eckert dimensionless number and a decrease in Prandtl lead to an increase in temperature profile. Also, its noted that the concentration decreases with increasing Lewis number parameters and Brownian motion. It was found that with increasing magnetic effects, the rate of velocity profile also increases. This means that the magnetic effects overcome the viscous effects of Williamson fluid and increase the velocity.

Lattice Boltzmann modeling of double-diffusive convection of dielectric liquid in rectangular cavity subjected to unipolar injection

The lattice Boltzmann method is used to study the double-diffusive convection caused by the simultaneous effect of the temperature gradient and concentration gradient of the dielectric liquid in a rectangular cavity in the case of unipolar injection of ions. Considering that the physical model in this article is a complex dynamic system, we first conducted a linear stability analysis and obtained a neutral stability curve. Then we made a series of simulations to determine the influence of different dimensionless parameters on the movement of dielectric liquids and the distribution of charge density, temperature field, and concentration field. The variation range of the parameters is as follows: thermal Rayleigh number (1000≤Ra≤20000), electric Rayleigh number (100≤T≤800), Lewis number (1.0≤Le≤50.0), and buoyancy ratio (−2≤Nc≤0.5). The results show that the increase in electric Rayleigh number and thermal Rayleigh number will enhance the intensity of heat and mass transfer. Compared with pure electric convection, the existence of temperature field and concentration field have increased the instability of the dielectric fluid flow. When the Lewis number increases, the average Nusselt number will decrease but the average Sherwood number will increase. In addition, we noticed that the heat and mass transfer intensities have increased with the increase of the buoyancy ratio. When the buoyancy rate gradually increases from –2.0, we observe a bifurcation structure, and as the electric Rayleigh number increases, the critical value Ncc that causes convection will decrease.

MHD mixed convection on an inclined stretching plate in Darcy porous medium with Soret effect and variable surface conditions

AbstractThis work is concerned with a steady 2D laminar MHD mixed convective flow of an electrically conducting Newtonian fluid with low electrical conductivity along with heat and mass transfer on an isothermal stretching semi-infinite inclined plate embedded in a Darcy porous medium. Along with a strong uniform transverse external magnetic field, the Soret effect is considered. The temperature and concentration at the wall are varying with distance from the edge along the plate, but it is uniform at far away from the plate. The governing equations with necessary flow conditions are formulated under boundary layer approximations. Then a continuous group of symmetry transformations are employed to the governing equations and boundary conditions which determine a set of self-similar equations with necessary scaling laws. These equations are solved numerically and similar velocity, concentration, and temperature for various values of involved parameters are obtained and presented through graphs. The momentum boundary layer thickness becomes larger with increasing thermal and concentration buoyancy forces. The flow boundary layer thickness decreases with the angle of inclination of the stretching plate. The concentration increases considerably for larger values of the Soret number and it decreases with Lewis number. The skin friction coefficient increases for increasing angle of inclination of the plate, magnetic and porosity parameters, however it decreases for rise of thermal and solutal buoyancy parameters. In this double diffusive boundary layer flow, Nusselt and Sherweed numbers increase for rise of thermal and solutal buoyancy parameters, Prandtl number, but they behave opposite nature in case of angle of inclination of the plate, magnetic and porosity parameters. The Sherwood number increases for increasing Lewis number but it decreases for increasing Soret number.

Oxytactic Microorganisms and Thermo-Bioconvection Nanofluid Flow Over a Porous Riga Plate with Darcy–Brinkman–Forchheimer Medium

Abstract The aim of this paper is to analyze the behavior of oxytactic microorganisms and thermo-bioconvection nanofluid flow through a Riga plate with a Darcy–Brinkman–Forchheimer porous medium. The Riga plate is composed of electrodes and magnets that are placed on a plane. The fluid is electrically conducting, and the Lorentz force evolves exponentially along the vertical direction. The governing equations are formulated with the help of dimensionless variables. With the aid of a shooting scheme, the numerical results are presented in graphs and tables. It is noted that the modified Hartmann number boosts the velocity profile when it is positive, but lowers these values when it is negative. The density-based Rayleigh number and the nanoparticle concentration enhance the fluid velocity. The thermal Rayleigh number and the Darcy–Forchheimer number decrease the velocity. An increase in Lewis number causes a remarkable decline in the oxytactic microorganism profile. Several useful results for these flows with oxytactic microorganisms through Darcy–Brinkman–Forchheimer porous media are presented in this paper.

Experimental assessment of heat and mass transfer characteristics of solar-powered adiabatic liquid desiccant dehumidifier and regenerator

Abstract Coupled heat and mass transfer performance of an adiabatic solar-powered liquid desiccant dehumidification and regeneration scheme using lithium bromide(LiBr) solution has been conducted experimentally as well as numerically under subtropical climatic conditions. The application of a vacuum insulated photovoltaic and thermal module to provide desiccant regeneration heat as well as electrical power to drive the air fans and liquid pumps have been explored. A square channelled ceramic cordierite packing with a varying channel density of 20–80 m$^2$/m$^3$ has been used to establish the optimum direct air-LiBr contact ratio for maximum effectiveness. The aggregate crammed vertical dehumidifier and regenerator operational indices featured were effectiveness, moisture removal rate (MRR), heat and mass transfer constants and Lewis number. The influence of solar radiation, humidity and L/G ratios, air–desiccant flow rates and concentration on the indices have been scrutinized in details. A 3D predictive numerical thermal model based on falling liquid stream with constant thickness in counter-flow configuration has been developed and solved by a combination of separative appraisal and stepwise iterative technique. The heat and mass exchange coefficients significantly increased with the increase in Lewis number, air and desiccant flow rates for both the dehumidifier and regenerator vessels. The predicted results of heat and mass transfer coefficients, effectiveness and MRRs have been validated with experimental measurements within a general acceptable conformity of less than $\pm $10%.