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Besides discussing such seminal images in the poetry of Daud Kamal as Gandhara art, the bridge, and bird migration, this essay explores solitude as a necessary accompaniment to Kamal’s creativity, as he sought, in “the translunar paradise of art”, “a cure for the cancer of loneliness”. This essay also examines the undiscerning critical reception of Kamal’s poetry, which notwithstanding belongs to the finest tradition of Islamic mystical poetry and is therefore destined to last.

The convective flows through different geometries have numerous applications in high-speed aerodynamics, nuclear cooling systems, fiber technology, and polymer engineering. In the present paper, we investigate the non-linear, mixed convective, boundary-driven, tangent hyperbolic nanofluid flow through a cone. The flow takes place under nonuniform heat sink/source. Darcy-Forchheimer effects have also been taken into account in mathematical modeling and analysis. The Buongiorno model is implemented to examine the effects of thermophoresis and Brownian motion parameters. The governing equations are constructed through the laws of conservation. The modeled flow problem is converted into a set of ordinary differential equations with the help of proposed similarity transformations. To interpret the modified system of equations, the homotopy analysis method (HAM) is applied. The roles of versatile parameters of interest are analyzed and sketched for better understanding. The velocity profile increases by increasing the Darcy number, and converse behavior is found by giving rise to the Forchheimer inertial drag parameter. The rise in temperature profile occurs by increasing a non-uniform heat source variable. The concentration profile enhances when the value of the thermophoresis parameter increases, and shows inverse behavior for the Brownian motion parameter. In the Buongiorno model, nanoparticle concentration has an inverse relation with the Brownian motion parameter. So, the concentration profile declines for greater Brownian motion parameter. To understand the behavior of flow through a cone, the values of Nusselt number and Sherwood numbers are examined.

This research deals with the analysis of bioconvection caused by the movement of gyrotactic microorganisms. The multi-layer immiscible Newtonian fluid flowing through the vertical channel conveying tiny particles is accounted. The immiscible fluids are arranged in the form of a sandwich where the middle layer has a different base fluid that does not mix with the base fluid of the adjacent fluid layer. This separation of the fluid layers gives rise to the interface boundary conditions. Such flows have found applications in electronic cooling and solar reactors processes. Buongiorno’s model has been incorporated to design the mathematical model that describes the three-layer flows of Newtonian fluid conveying tiny (metal/oxide) particles under thermophoretic force and Brownian motion. The model thus formed is in the form of the ordinary differential system of equations that are solved using the DTM-Pade approximant after non-dimensionalization. The limited results have an excellent comparison with the existing literature results. The results are discussed through graphs and tables. It is seen that thermophoresis enhances the temperature and particle concentration of the fluid whereas, the Brownian motion is found to enhance the temperature and decrease the concentration. The presence of bioconvection helps in achieving enhanced energy and mass transportation. Moreover, the heat transfer occurring between the different base fluids helps to maintain the optimum temperature in the systems.

In the poetry of Daud Kamal, water figures as an image of mercy, as in the Quran, and as a mirror that reflects a divine hidden presence. The rock pool evokes the memory of Gandhara and other foundational civilizations born in love and creative ferment. Conversely, the images of drought, heat, and dust symbolize a parched spiritual order. The river, a recurring archetypal image in Kamal’s poetry, represents the fluid self that is subsumed into collective identity to become a poetic distillate of history.

In this novel numerical investigation, the application of well-renowned numerical technique known as Galerkin finite element method on full form of Navier-Stokes equations presented peristaltic flow of non-Newtonian fluid confined by a uniformly saturated porous medium. The rheological aspects of non-Newtonian material are discussed by considering micropolar fluid. The flow model consists of system of nonlinear partial differential equations with mixed boundary condition. The flow also experienced an externally applied magnetic field. The effects of inertial forces and the results independent of wavelength are obtained by dropping the presumptions of lubrication theory in modelling the governing equations. The numerical solution for formulated problem in terms of partial differential expressions is worked out via Galerkin finite technique in view of six nodal triangular elements. The enhancement in the inertial forces gives impressive pressure enhancement against wavelength while opposed the fluid flow in the vicinity of peristaltic walls of the tube but supported the fluid flow in the central region of the tube. The present results are also compared with the available results after applying lubrication theory and found in reliable agreement.

This research explored the influences of entropy generation on bioconvected nanoliquid flow through the porous cavity filled with nanofluid and gyrotactic microbes. The porosity term in the momentum equation is summarized by the implementation of Darcy’s formula through Boussinesq estimation. The novelty of this study is to investigate entropy generation in cavity by augmenting the convection generated by the phenomenon of Brownian motion, thermophoresis of nanofluid flow and the bioconvection due to swimming of microorganisms. The governing partial differential equations (PDEs) are highly nonlinear and are nondimensionalized through the suitable similarity constraints. The transformed PDEs are tackled via implementation of finite difference method (FDM). The reaction of entropy generation and Bejan number against various quantities like bioconvection Rayleigh number ([Formula: see text]–100), Rayleigh number ([Formula: see text]–100), Peclet number ([Formula: see text]–0.9) and ratio of buoyancy ([Formula: see text]–1) are reported and visualized. The entropies by theliquid friction, heat transportation, mass transmission and microorganisms are focused. Upsurge in Nr (0.3–0.5) and Pe (0.1–0.15) accelerated the maximum of entropy due to microorganism by 7% and 44%, respectively. Here, an increment in Ra, Rb, Pe and Nr affects the distribution pattern of total entropies and Bejan number consistently. The higher Lewis number caused a decrement in the total entropy by liquid friction.

Purpose This study aims to use the thermal non-equilibrium approach to inquire the entropy production and conjugate natural heat exchange in a porous medium. Entropy generation is studied separately for the solid matrix and the hybrid nanoliquid. Design/methodology/approach The characteristic equations are unraveled by applying the finite element method. Mathematical relations are used to calculate the generated entropy for the hybrid nanoliquid and matrix structure. Findings Based on the results, the produced entropy and the viscous friction term associated with the hybrid nanoliquid phase are not affected by increasing the thermal conductivity ratio of the rigid wall to nanoliquid. Moreover, a higher amount of entropy is generated by the thermal gradients in the hybrid nanoliquid phase compared to the solid matrix. Originality/value No investigation in the literature has been reported in this context.

Protocol for a scoping review of applications of machine learning models related to communicable diseases in population and public health

Protocol for a scoping review of machine learning applications related to public and population health, focused on common non-communicable diseases

This paper deals with the boundary element method solution of set of parabolic differential equations of heat conducting problems with continuous and discontinuous boundary conditions. Time-dependent terms have been used as a non-homogeneous forcing function by changing a parabolic differential equation into a Poisson's equation. The suggested approach for solving the Poisson equation has been modified which decreases the number of algebraic equations and reduces the computational time. The constant coefficient matrix and LU decomposition provide an economical means for the solution of the concern problem. The discretization of the boundary of parabolic differential equations with respect to (w.r.t.) time is one of the main features of this article. Direct determination of unknown at interior points is also trademark of the proposed method. The method has been supported by examples, which include discontinuous boundary conditions and non-homogeneous forcing terms to highlight its effectiveness and accuracy.

[Formula: see text] nanolubricant is one of the most important nanolubricants having widespread uses in heat exchange systems and automobiles. It minimizes friction between moving parts and prevents them from corrosion and scrape, improves durability and performance of the system and also minimizes the consumption of fuel. This work investigates the rheological behavior of magnetized [Formula: see text] nanolubricant over moving/stationary Riga plate with viscous dissipation and nonlinear heat generation. The novel features of the current work are the use of [Formula: see text] nanolubricant as a flow fluid across a Riga plate and the application of the Patel model to boost the thermal conductivity of the nanolubricant. The governing system of equations is transformed to nonlinear ODEs and then treated analytically by using HAM. The augmentation in the velocity of nanolubricant [Formula: see text] is observed due to increasing values of Grashof number. The higher values of nonlinear thermal radiation and nonlinear heat generation parameters upsurge the temperature profile. The value of skin friction increases by increasing modified Hartman number and velocity slip parameter while reverse trend is observed by enhancing magnetic parameter. The radiation parameter, temperature dependent heat source parameter and solid volume fraction tend to augment Nusselt number at the Riga surface.

With the development of problems caused by burning fossil fuels as well as limited and exhaustible energy resources, there is a growing interest in clean and renewable energies as a reliable alternative to fossil fuels. The thermal performance of a dual-porous heat exchanger (SDPHE) in building heating is investigated in this article. The characteristic equations for both porous media and the solid wall are discretized and solved numerically by finite element method (FEM) based on finite volume. The efficacy of various parameters including the Reynolds number, Darcy number and porosity of both porous media, middle wall thickness, middle wall material and volume fraction on the thermal performance of dual-porous heat exchanger is demonstrated and interpreted. According to the results, as the Darcy number and the congestion of nanoparticles on each side increased, the effectiveness of dual-porous heat exchanger is increased. In contrast, an increase in porosity on each side caused a decline in the effectiveness of dual-porous heat exchanger. Moreover, the thermal performance first increased and then reduced with an increase in hot side Reynolds number.

Purpose The purpose of this paper is to address the impact of gravity induced stretching flow of second grade liquid subject to thermal radiation. The flow is generated by the stretching of an impermeable cylinder. Stagnation point flow is considered. Convective type boundary conditions are applied on temperature and concentration. The present investigation further includes the aspects of magnetohydrodynamics, Joule heating, chemical reaction and viscous dissipation and heat generation/absorption. Design/methodology/approach The ordinary differential expressions are formed using suitable similarity transformations from the governing partial differential expressions. The subsequent nonlinear ordinary differential expressions are solved analytically using homotopy concept to report the consequences of different dimensionless physical parameters in graphical and tabular forms. Findings The results witnessed that increasing values of curvature parameter corresponds to higher temperature and concentration. Besides this, the impacts of destructive and constructive chemical processes on the concentration distribution are noted opposite. Originality/ No such analysis has yet been reported.

The structure of needle is mostly similar as paraboloid of upset parallel to flow possesses and has huge applications in building and modern procedures including microstructure electronic gadgets and microscale cooling gadgets for thermal evacuation application. Based on these applications, an axisymmetric Darcy–Forchheimer flow and energy transport of hybrid nanoliquid over a slender moving needle is considered. Impact of heat sink/source and Newtonian heating is inspected. The dimensional nonlinear administering partial differential equations (PDEs) are modified to dimensionless nonlinear ordinary differential equations (ODEs) with assistance of similarity technique which is then explained numerically utilizing Runge–Kutta–Fehlberg scheme from Dsolve code MAPLE. It ought to be noticed that approval of results shows a decent concurrence with previously existing reports. It is noticed that the enhancing Forchheimer number and porosity parameter increase the temperature.

The enhancement of energy by introducing nanoparticles is a hot topic in the present century, due to industrial and technological applications. Therefore, current article investigates the peristaltic flow of $$\mathrm{Ag}{-}\mathrm{H}_2\mathrm{O}$$ nanofluid with entropy generation through a uniform channel. Hall and Radiation effects are incorporated. Two-phase formulation for nanofluid is employed. Long-wavelength approximation is used in the mathematical modelling. Built-in numerical solver NDSolve is utilized. Numerical results of the coupled equations are sketched for several quantities of interest. Outcomes of the study reveals that entropy significantly reduces for large values of Hall parameter, whereas opposite behaviour is noted for velocity. Increase in the values of radiation parameter reduces the velocity, temperature, and entropy generation. Increase in Bejan number is observed for enhancement in Brinkman number. Rate of heat transfer at walls increases when heat source parameter is increased. Additionally, comparison of different nanoparticles is also furnished through tables.

The basic idea of the present article is to model and study the aspects of curvature-dependent channel walls on peristalsis of laminar viscous material flow through a curved geometry. Mathematical modeling for such flow configuration is being presented for the first time. Lubrication theory assumptions are used for mathematical modeling of the problem. Moreover, the numerical method is used to solve the resulting system of equation. The impacts of different flow quantities on the heat transfer rate, velocity and temperature profiles are discussed via graphs. Results indicate that the curvature parameter considerably influences the mechanical and thermal aspects of the flow and hence must be included in the modeling of flows through curved a channel.

In current attempt, a numerical code was developed to model the nanofluid free convected magnetized flow by porous cavity. Non-Darcy formula is carried out to include the term of porosity in momentum expression. Radiative phenomenon is reported for distinct nanoparticle shapes. Aspects of radiative constraint, shape factor, Rayleigh number, magnetic force, and nanoparticles’ shape on nanofluid magneto-hydrodynamic natural convection are analyzed. Result demonstrated that application of external magnetic force deteriorates the convection and this reduction is more perceptible at the greater permeability. The conductive heat transport is the dominating form of heat transportation under the impact of higher magnetic force. For the constant values of Rayleigh, Hartmann’s and Darcy number, $${\text{Nu}}_{{{\text{avg}}}}$$ is independent of shape factor and observes a direct association with the radiation parameter.

Among the fabrication of the nano-biometerials, the bioconvection of nanoparticles attained the utmost importance in this decade. Therefore, this theoretical continuation is performed to utilize the bioconvected flow of Williamson nanofluid caused by an oscillatory stretching surface. The flow is generated due to periodic motion of the sheet. The energy equation is modified by variable thermal conductivity. The significance of present flow problem increases by utilizing the thermophoresis and Brownian movement factors. The available formulated partial differential equations are promoted into non-dimensional structure via similarity variables. The analytical solution is fulfilled using convergent technique. The implications of promising parameters on velocity, temperature profile, nanoparticles volume fraction and microorganisms profile are evaluated graphically. Locally constituted physically expressions such as Nusselt number, Sherwood number and motile density number are treated numerically as well as graphically. The presence of variable thermal conductivity, thermophoresis and Brownian motion effects are more frequent for enhancement of heat transfer. The detected observation can involve the theoretical significance in various engineering processes, bio-fuel cells, solar energy system and enhancement of extrusion systems.

The scenario of this attempt is to elucidate the nature of hydrodynamic hybrid nanofluid over a moving frame. Solar radiation and the spherical shape particle are implemented. The implication of suitable transformation corresponds to self-similarity equations. Least square and RKF 45th-order techniques are employed to evaluate these non-dimensional equations. For better understanding of the problem, energy and flow features are demonstrated for distinct physical constraints. It is recognized that the transfer of fluid heat is pronounced for enhancing but dismisses in rising values of . The larger generates more heat in liquid that results in improvement of temperature.

The non-Darcy heat transportation of the ferrofluid together with the entropy generation has been studied in a permeable zone under the role of magnetic force. To incorporate the permeable impact, the non-Darcy approach was utilized. CVFEM-based code is implemented to explore the entropy generation and heat transportation for the parametric ranges of Rayleigh (Ra), Darcy (Da) and Hartmann (Ha) numbers. The results demonstrate that here the conduction is the significant mode of transportation of heat at higher Ha; however, the increment in Ra and Da promotes the convection. The Bejan number increases at higher Ha and it decreases with the augmentation of Ra and Da. The enhancement of Ra and Da results in the declination of $$X_{{\rm d}}$$ , and it escalates under the impact of stronger Ha.

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Marangoni convection is very useful in coating flow technology, surfactant replacement therapy for neonatal children, microfluidics, drying of semi-conductor vapors in microelectronics, foams, and film drainage in emulsions. The behavior of gyrotactic microorganisms and chemical reaction on the Marangoni convected Carreau-Yasuda liquid flowing over Riga plate with thermophoretic particle deposition is reported in this research. The Riga plate is self-possessed of magnets and electrodes. The fluid conducted electricity and the vertical Lorentz force has been exponentially increased. Thermal and mass species phenomena are investigated within the context of Dufour and Soret impacts. The PDEs are transformed into ODEs by the implication of suitable transformations. The resulting system of equations is solved by using homotopy analysis method (HAM). Using tables and graphs, the effects of dimensionless parameters on flow fields are described. The wall drag coefficient and pertinent flow rates are organized and stated. The results revealed that the temperature, concentration, and microorganisms profiles decay but the velocity profile augmented as the Marangoni ratio parameter increases.

Purpose An increment in energy efficiency by employing nanoparticles is a hot topic of research in present era due to its abundant implications in modern engineering and technological processes. Therefore, the current research analysis reported the viscoelastic nanofluid flow over porous oscillatory moving sheet in the presence of microorganisms. A rate-type fluid namely Maxwell fluid is employed with the addition of nanoparticles. The paper aims to discuss this issue. Design/methodology/approach First, acceptable dimensionless variables are defined to convert the system of dimensional form into the system of dimensionless forms. Later on, the self-similar solution of the boundary value problem is computed by using the homotopy analysis method. The obtained results of velocity, temperature, mass concentration and motile microorganism density profiles are interpreted through physical background. Findings The presence of both thermophoresis and Brownian motion parameters also improve the thermophysical features of non-Newtonian nanoparticles. It is also pointed out that the presence of porous medium and magnetic force enhances the nanoparticles concentration. Moreover, a weaker distribution of gyrotactic microorganism has been depicted with Peclet number and bioconvection Lewis parameter. Originality/value No such article exists in the literature yet.

In this paper, stagnation point region (suspended with nanofluid and microorganisms) is examined subjected to velocity and thermal slips. The flow is assumed to be flowing across an exponentially stretching flat surface under magnetic field environment. Governing transport equations (framed under Buongiorno's model) are converted into self-similar form through suitable unsteady exponential similarity transformations which are then solved by employing implicit finite difference scheme (IFDS) known as Keller-box method (KBM). A parametric analysis is performed along with limited details of KBM. Influence of pertinent constraints on local skin friction, local Nusselt number, local Sherwood number and local density number of micro-organisms are also uncovered through graphs. A significant decrease in skin-friction coefficients has been detected with respect to thermal slip in comparison to velocity slip. Keywords: Unsteady flow, Stagnation point region, Mixed convection, Microorganisms, Nanoparticles, Slip regime, Keller-box scheme

The main aim of the current paper is to investigate the mass and heat transportation of a Casson nanomaterial generated by the inclination of the surface. The magnetic field effect along with suction or injection are considered. The working nanomaterial is taken into consideration based on the concept of the Buongiorno nanofluid theory, which explores the thermal efficiencies of liquid flows under movement of Brownian and thermophoretic phenomena. The emergent system of differential expressions is converted to dimensionless form with the help of the appropriate transformations. This system is numerically executed by the implementation of Keller–Box and Newton’s schemes. A good agreement of results can be found with the previous data in a limiting approach. The behavior of the physical quantities under concern, including energy exchange, Sherwood number, and wall shear stress are portrayed through graphs and in tabular form. The Nusselt number and Sherwood number are found to diminish against the altered magnitudes of Brownian motion and the inclination parameter. Moreover, the velocity profile decreases with the growth of the inclination effect. In the same vein, the buoyancy force and solutal buoyancy effects show a direct relation with the velocity field. The outcomes have promising technological uses in liquid‐based systems related to stretchable constituents.

This manuscript is aimed at investigating the thermohydraulic characteristics of Al2O3 − Cu/water hybrid nanofluid in a micro pin-fin heat sink by implementing a multiphase Lagrangian–Eulerian approach. In modelling the nanofluid the influence of slip mechanisms i.e. Saffman lift and drag force, Brownian motion, gravity, virtual mass, thermophoresis and pressure gradient-induced force is included. In addition, the fin efficiency of the nanofluid cooled sharp and streamlined fin configurations is probed by analysing diamond, circular and elliptical fins arranged in the staggered assembly. Spherical shaped hybrid nanoparticles of 15 nm are studied for the particle volume fraction of 1%. The performance of heat sinks is evaluated by analysing the quantitative parameters including log mean temperature difference, average (Nuavg) and surface (Nus) Nusselt number. Besides, the flow streamlines, thermal and vorticity contours represent the qualitative depiction of flow and thermal distributions. Results demonstrate that utilising nanofluid optimises Nuavg enhancement to maximum values of 25.14%, 19.65% and 24% for diamond, circular and elliptical fins, respectively. The thermal efficiency of nanofluid is highest across the upstream fins and it diminishes towards the downstream fins. At the highest pressure drop, the fin efficiency of the studied fin configurations is in the order of circular, elliptical and diamond fins.

Purpose The purpose of this study is to scrutinize the effects of entropy generation and nonlinear mixed convection on the boundary layer flow of second grade fluid induced by stretching sheets. Heat transfer effects are accounted in view of viscous dissipation and nonlinear thermal radiation. Design/methodology/approach Optimal homotopic asymptotic method procedure is adopted to obtain the analytical solution of nonlinear ordinary differential equations. Findings It has been noticed that Hartmann and Brinkman number has reverse characteristics against entropy generation and Bejan number. Originality/value To the best of the authors’ knowledge, no such analysis has been reported to date.

In the 1980s, during General Zia ul-Haq’s dictatorship, Daud Kamal (1935–1987) published English-language translations of progressive Urdu poetry in the Pakistani dailies The Muslim and The Pakista...