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This investigation uses the Tiwari and Das nanofluid model to enhance the heat transfer rate in Sutterby nanofluid over a Riga plate. The effects of heat source/sink, viscosity dispersion, and mass flow for water-based fluids are also considered in this work. Sutterby fluid has been utilized to investigate the rheological features of nanofluids. The transverse Lorentz force produced by the Riga plate assists in the flow down the plate by producing an electromagnetic field. The main aim of this investigation is to evaluate the presence of two different types of nanoparticles in water, specifically silicon carbide (SiC) and copper (Cu). Dimensionless variables are first used to convert the mathematical model into a non-dimensional form. The similarity approach is then used to further rewrite the non-dimensional partial differential equations into a set of similarity equations. The bvp4c function in MATLAB software provides a numerical solution to these equations. The effects on temperature and velocity profiles of many physical factors, including the Reynold number, heat source/sink, and Deborah number, have been analyzed and presented. Furthermore, using tables, a detailed analysis of the skin friction coefficient and local Nusselt numbers is conducted. The results show that convective flow is suppressed when solid nanoparticles are added to the base fluid. The velocity distribution improves as Deborah and Reynold's numbers get a higher value. Also, the temperature field improves by incrementing exponential and thermal heat source/sink parameters. [ABSTRACT FROM AUTHOR]

Microorganism movement may boost the convective transfer of heat by stirring the fluid to encourage mixing. Engineers may improve heat dissipation and maintain temperatures in electrical devices, engines, and industrial machinery by varying microbe proportion and quality. This research aims to gain insight into the rheological effects of an Eyring–Powell nanofluid and the movement of gyrotactic microorganisms on the surface of the Riga plate. The propagation of linear and non‐linear mixed‐convection nanofluid through a Riga plate is also studied. The primary goal of this work is to accelerate the heat transfer rate of nanofluid. The efficiency of heat transport and the ability to postpone boundary layer separation are both influenced by the magnetohydrodynamic force produced by the Riga plate. Regulating problem is converted into dimensionless form using suitable transformations, and the resulting equations are then resolved numerically using the MATLAB program "bvp4c". The simulations are run for various variables, such as Prandtl numbers, mixed convection parameters, Hartmann numbers, Reynold numbers, Peclet numbers, and Lewis numbers. The outcomes are presented both tabularly and visually. This evaluation shows an increment in the Eyring–Powell fluid and mixed convection parameters, which causes the velocity profiles to rise. However, the reverse is true for an escalation in the magnetic parameters. In addition, the activation energy parameter increases the concentration profile. On the other hand, the Eyring–Powell fluid parameter causes the thermal field to contract. The skin friction at Nt=0.5$Nt=0.5$ is 45.13% and decreased by 24.07% when Nt=2.9$Nt=2.9$ for the linear case, while for the quadratic case, it is 43.69% at Nt=0.1$Nt=0.1$ and deceased 25.58% when Nt=2.9$Nt=2.9$. A comparison against an earlier study is also performed to determine the accuracy of the proposed model. An outstanding agreement between current findings and formerly existing solutions shows the legitimacy of the present discoveries. [ABSTRACT FROM AUTHOR]

AbstractThis manuscript investigates the comparative analysis of SiC and SiC−Ag with methanol-base fluid. The nano species are more important in many fields such as medicine, catalysis, energy-based research, imaging, and environmental sciences. The present study includes theoretical and numerical studies of the Prandtl hybrid nanofluid flow model, which takes into account the effects of heat radiation across a stretched cylinder, inclined magnetohydrodynamics (MHD), and Darcy-Forchheimer. The cylinder’s surface is subjected to the convective slip boundary condition as part of the study. The main aim of this study is to enhance heat transformation. The flow problem is formulated in a system of nonlinear partial differential equations. By employing a similarity transformation, a nonlinear system of partial differential equations can be converted into a linear system of ODEs. A feasible numerical technique Bvp4c is used to solve the reduced system of ODEs through MATLAB software. The results of temperature, concentration, and velocity profiles are discussed graphically. In section and injection scenarios, the velocity profile of both fluids decreased with increasing inputs of magnetic and Darcy-Forchheimer parameters. The heat transmission improved for higher inputs of Prandtl and thermal radiation parameters for both section and injection cases. Furthermore, our findings align with the body of current literature. The conclusions are supported by a careful comparison with pertinent research that has been published in earlier publications. [ABSTRACT FROM AUTHOR]

The enhanced power quality provided by multilevel inverters (MLIs) has made them more appropriate for medium- and high-power applications, including photovoltaic systems. Nevertheless, a prevalent limitation involves the necessity for numerous switches and increased voltage stress across these switches, consequently increasing the overall system cost. To address these challenges, a new 17-level asymmetrical MLI with fewer components and low voltage stress is proposed for the photovoltaic system. This innovative MLI configuration has four direct current (DC) sources and 10 switches. Based on the trinary sequence, the proposed topology uses photovoltaics with boost converters and fuzzy logic controllers as its DC sources. Mathematical equations are used to calculate crucial parameters for this proposed design, including total standing voltage per unit (TSVPU), cost function per level (CF/L), component count per level (CC/L) and voltage stress across the switches. The comparison is conducted by considering switches, DC sources, T S V P U ⁠ , CF/L, gate driver circuits and CC/L with other existing MLI topologies. The analysis is carried out under various conditions, encompassing different levels of irradiance, variable loads and modulation indices. To reduce the total harmonic distortion of the suggested topology, the phase opposition disposition approach has been incorporated. The suggested framework is simulated in MATLAB®/Simulink®. The results indicate that the proposed topology achieves a well-distributed stress profile across the switches and has CC/L of 1.23, T S V P U of 5 and CF/L of 4.58 and 5.76 with weight coefficients of 0.5 and 1.5, respectively. These values are notably superior to those of existing MLI topologies. Simulation results demonstrate that the proposed topology maintains a consistent output at varying irradiance levels with FLCs and exhibits robust performance under variable loads and diverse modulation indices. Furthermore, the total harmonic distortion achieved with phase opposition disposition is 7.78%, outperforming alternative pulse width modulation techniques. In summary, it provides enhanced performance. Considering this, it is suitable for the photovoltaic system. [ABSTRACT FROM AUTHOR]

Multilevel inverters (MLIs) have recently attracted more attention in medium-voltage and high-power applications as they can provide an effective interface with photovoltaic (PV) systems. Conventional MLIs are used to generate higher voltage levels, which improve power quality and reduce the requirement for passive filters. However, recent research has focused on designing new MLI topologies using reduced switch counts and less voltage stress. This study, as such, proposes a new nine-level symmetric MLI for PV systems with a minimum number of switches. This decrease in the number of switches reduces the voltage stress across the switches and the number of driving circuits, which lowers the complexity of the control circuit and, as a result, lowers the cost and size of the system. This article compares the proposed MLI with other topologies based on the DC sources, switches count, gate driver circuits (Ngd), total standing voltage per unit (TSVPU), cost function (CF), and components count per level (CC/L). The proposed topology is integrated with the PV system. MATLAB software is used to evaluate the performance of MLI at step change in irradiance and under variable load conditions. The total harmonic distortion (THD) of the proposed topology is reduced with the implementation of phase disposition pulse width modulation (PD-PWM). In addition, PD-PWM is compared with phase opposition disposition pulse width modulation (POD-PWM) and alternative phase opposition disposition pulse width (APOD-PWM) modulation techniques. The simulation results reveal the improved performance of the proposed topology at variable irradiance and under varying load conditions. The comparison results reveal minimum (TSVPU), CC/L, CF, and switch count compared to existing topologies. Hence, the proposed topology of MLI is cost-effective and superior in all aspects compared to other topologies. In summary, it offers overall improved performance, and thus, it is feasible for the PV system. [ABSTRACT FROM AUTHOR]

This study aims to determine the heat transfer properties of a magnetohydrodynamic Prandtl hybrid nanofluid over a stretched surface in the presence of bioconvection and chemical reaction effects. This article investigates the bio-convection, inclined magnetohydrodynamic, thermal linear radiations, and chemical reaction of hybrid nanofluid across stretching sheets. Also, the results are compared with the nanofluid flow. Moreover, the non-Newtonian fluid named Prandtl fluid is considered. Microfluidics, industry, transportation, the military, and medicine are just a few of the real-world applications of hybrid nanofluids. Due to the nonlinear and convoluted nature of the governing equations for the problem, similarity transformations are used to develop a simplified mathematical model with all differential equations being ordinary and asymmetric. The reduced mathematical model is computationally analyzed using the MATLAB software package's boundary value problem solver, Runge-Kutta-fourth-fifth Fehlberg's order method. When compared to previously published studies, it is observed that the acquired results exhibited a high degree of symmetry and accuracy. The velocity profiles of basic nanofluid and hybrid nanofluid are increased by increasing the Prandtl parameters' values, which is consistent with prior observations. Additionally, the concentration and temperature of simple and hybrid nanofluids increase with the magnetic parameter values. [ABSTRACT FROM AUTHOR]

Hamilton–Jacobi ansatz is used to analyze boson charged particles tunneling in Rastall gravity Kerr–Newman black hole (BH) surrounded by perfect fluid matter through the horizon. The geometrical BH parameters are observed, how these are affecting the radiation utilizing the Lagrangian gravity equation. In this paper, the corrected Hawking temperature is computed by considering the effects of quantum gravity. In our analysis, the Rastall gravity BH solution surrounded by perfect fluid matter effects on Hawking radiation is analyzed graphically. Moreover, the stability and instability of Rastall gravity BH are investigated. The influence of quantum gravity and rotation parameters on BH radiation are also observed by graphical representation. [ABSTRACT FROM AUTHOR]

This paper provides an extension for Hawking temperature of Reissner–Nordström-de Sitter (RN-DS) black hole (BH) with global monopole as well as 5 D charged black hole. We consider the black holes metric and investigate the effects of quantum gravity (α) on Hawking radiation. We investigate the charged boson particles tunneling through the horizon of black holes by using the Hamilton–Jacobi ansatz phenomenon. In our investigation, we study the quantum radiation to analyze the Lagrangian wave equation with generalized uncertainty principle and calculate the modified Hawking temperatures for black holes. Furthermore, we analyze the charge and correction parameter effects on the modified Hawking temperature and examine the stable and unstable condition of RN-DS BH with global monopole as well as 5 D charged black hole. [ABSTRACT FROM AUTHOR]

We explore the Lagrangian equation in the background of generalized uncertainty principle. The tunneling radiation through the black ring horizon is observed. We investigated the tunneling radiation through the Hamilton–Jacobi method for solutions of Einstein–Maxwell-dilation gravity theory. The radiation of black ring without back reaction and self-interaction of particles are studied. Furthermore, we consider the quantum gravity effect on the stability of black ring. [ABSTRACT FROM AUTHOR]

In this paper, we study the behavior of non-interacting and interacting pilgrim dark energy (DE) for non-flat FRW model in Brans–Dicke (BD) theory. We consider the future event horizon as well as logarithmic form of BD scalar field ψ ∝ ln (γ + δ a) , where γ > 1 , δ > 0 and a is the scale factor. We evaluate some well-known cosmological parameters such as equation of state as well as deceleration parameter and ω Λ − ω Λ ′ plane as well as statefinder parameters. We discuss graphical behavior of these parameters through pilgrim DE parameter μ = − 1. 2 , 1 , 1. 2 for both non-interacting as well as interacting case with interacting parameter b 2 = 0. 0 2 , 0. 5 , 1. It is found that the equation of state parameter gives consistent results with the current cosmic behavior while the deceleration parameter represents transition from decelerated to accelerated phase. The cosmological planes represent different DE regions. Finally, we discuss stability of the model through squared speed of sound in both cases. [ABSTRACT FROM AUTHOR]

The current research evaluates the thermophysical characteristics of a rotational Williamson hybrid nano-liquid in three dimensions with Darcy-Forchheimer, magnetic field, nonlinear thermal radiation, activation energy, dual stratifications, and suction/injection effects on a stretched surface. The heat transmission enhancement is primary focus of the current study. Single-wall and multi-wall carbon nanotubes are combined with the base fluid C 2 H 6 O 2 - H 2 O to form a hybrid fluid. Tiny particles are studied because of their unique characteristics, like excellent thermal conductivity, which is crucial in contemporary nanotechnology, cooling systems, cancer treatment, material sciences, and electrical components. Partial differential equations define flow models, and these equations are converted into ordinary differential equations by a workable similarity transformation due to the nonlinear nature of the resulting governing differential equations. The Runge–Kutta method is used to solve the mathematical structure numerically. The obtained results revealed a high degree of symmetry and precision compared to previously published studies. The primary velocity of hybrid nanofluid decreased and the secondary velocity of hybrid nanofluid increased for increasing the Williamson parameter values. The temperature as well as concentration profiles of hybrid nano-liquid are reduced for boosted values of stratification parameters. Moreover, Nusselt number, skin friction coefficient along y-axis and Sherwood number of Williamson hybrid nanofluid are declined with incremental in magnetic parameter. [ABSTRACT FROM AUTHOR]

The current research investigates the effects of Brownian motion, thermophoresis, and multi buoyancy forces on MHD Prandtl fluid as it flows through a stretched cylinder with convective boundary conditions. Linear thermal conductivity is included in the energy equation's development. The nanofluid flows are important in cooling systems, modern nano-technology, electronic parts and heat exchangers. The primary objective of this research is to enhance heat transportation. The problem consists of nonlinear PDEs and these equations are transformed into ODEs by incorporating suitable similarity transformations. The shooting strategy is used to solve the problem numerically after converting the non-dimensional ordinary differential equations to a system of first-order ODEs. A comparison is made between the MATLAB-generated findings and those that have already been published. The numerical results of various parameters have been systematically organized into tabular representations. Graphs show how significant parameters affect the given velocity, temperature, concentration, and motile microorganism measurements. When the buoyancy ratio and bio-convective Rayleigh number increase, the velocity profile drops; however, the temperature profile shows increasing behavior for the thermal radiation parameter. The concentration profiles are enhanced for the higher inputs in curvature parameter, magnetic parameter, and activation parameter while the density of motile microbes' decay for enhanced inputs of bio-convective Lewis number. [ABSTRACT FROM AUTHOR]

The rising challenges of thermal transportation in compact density heat exchangers demand an efficient solution. The adequate thermal transportation for various heat exchangers can be achieved by mild homogeneous mixing of metallic/nonmetallic materials in the bulk base fluid. In this way, the base fluid's thermal efficiency is boosted. So, hybrid nanofluid constituted by mixing two or more nano species in the bulk base fluid is more effective than nanofluids. Therefore, the current research aims to determine the heat transfer properties of a 3D rotating Williamson hybrid nanofluid with Darcy-Forchheimer, dual stratifications, nonlinear thermal radiation, magnetic field, viscous dissipation, activation energy, and Joule heating effects for a stretched surface. The Al 2 O 3 and Zn nanoparticles are mixed with base fluid C 2 H 6 O 2. Partial differential equations are used to formulate the flow problem. Due to the nonlinear nature of the resulting governing differential equations, these partial differential equations are converted into ordinary differential equations using a feasible similarity transformation. The reduced mathematical structure is solved numerically with the help of MATLAB software Bvp4c package's boundary value problem solver. This study showed a higher degree of symmetry and accuracy of data than the previous ones. The primary velocity declined, and secondary velocity was enhanced for nanofluid and hybrid nanofluid by increasing the Williamson parameter's values, which is consistent with prior observations. Additionally, the temperature and concentration of both fluids are decreased for the boosted inputs of thermal stratification and concentration stratification parameters, respectively. [ABSTRACT FROM AUTHOR]

We study the electromagnetic field equation along with the WKB approximation. The boson tunneling phenomenon from charged rotating black ring (CRBR) is analyzed. It is examined that reserve radiation consistent with CRBR can be computed in general by neglecting back reaction and self-gravitational of the radiated boson particle. The calculated temperature depends upon quantum gravity and CRBR geometry. We also examine the corrected tunneling rate/probability of boson particles by assuming charge as well as energy conservation laws and the quantum gravity. Furthermore, we study the graphical behavior of the temperature and check the stability and instability of CRBR. [ABSTRACT FROM AUTHOR]

We investigate the massive vector field equation with the WKB approximation. The tunneling mechanism of charged bosons from the gauged super-gravity black hole is observed. It is shown that the appropriate radiation consistent with black holes can be obtained in general under the condition that back reaction of the emitted charged particle with self-gravitational interaction is neglected. The computed temperatures are dependant on the geometry of black hole and quantum gravity. We also explore the corrections to the charged bosons by analyzing tunneling probability, the emission radiation by taking quantum gravity into consideration and the conservation of charge and energy. Furthermore, we study the quantum gravity effect on radiation and discuss the instability and stability of black hole. [ABSTRACT FROM AUTHOR]

The purpose of the current work is to determine how a magnetic field, nonlinear thermal radiation, a heat source or sink, a Soret, and activation energy affect bio-convective nanofluid flow across a Riga plate in terms of heat transfer qualities. The major goal of this investigation is to enhance the heat transfer rate. The flow problem is demonstrated in the form of a collection of PDEs. Since the generated governing differential equations are nonlinear, we use a suitable similarity transformation to change them from partial to ODEs. The bvp4c package in MATLAB is used to numerically solve the streamlined mathematical framework. The impacts of numerous parameters on temperature, velocity, concentration, and motile microorganisms profiles are examined through graphs. Whereas, skin friction and Nusselt number are illustrated using tables. As the magnetic parameter values are raised, the velocity profile is seen to decrease and the temperature curve exhibits the opposite tendency. Additionally, the heat transfer rate expands as the nonlinear radiation heat factor is enhanced. Moreover, the outcomes in this investigation are more consistent and precise than in earlier ones., (© 2023 IOP Publishing Ltd.)