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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 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]