Due to ample engineering and industrial applications involving electrically conducting fluids, such as in magnetic flow control devices, thermal magnetic systems, magnetic filtration and separation, and fluid transport in curved rotating channels, the present study examines the impacts of pressure-induced instability characteristics and chaotic nature of Magneto-hydrodynamic fluid flow in a rotating curved square duct (CSD), incorporating Hall and ion-slip currents. The rotational speed (Ω_T) around the vertical axis of the duct is constant while a variable transverse magnetic field is applied perpendicular to the fluid. The numerical solutions are obtained through the spectral method as a primary tool supported by additional techniques, including Chebyshev polynomial expansions and the collocation approach for the Dean number 0 < Dn ≤ 6500 over the magnetic parameter (M) 0.5 ≤ M ≤ 50.0. It demonstrates that augmenting the magnetic parameter decreases the flux value, while the Hall and ion slip currents show the opposite effect, but no significant impacts are seen on the velocity distribution. The study also shows that the bifurcation zone shifts to higher Dn and gradually weakens, while the steady curve approaches symmetry as the magnetic field is intensified. Linear stability analysis shows that the linearly stable region steadily grows as M increases, and for $M\ge 32.63$, the flow becomes linearly stable. Time evolution computations are carried out to study the unsteady behavior of the flow, and it is predicted that the multi-periodic or chaotic flow progressively transforms into a steady-state nature with the augmentation of the magnetic parameter. The transient flow experiences various instabilities, including asymmetric 2- to 4-vortex solutions.

The continuous improvement of solar thermal technologies is essential to meet the growing demand for sustainable heat generation and to support global decarbonization efforts. This study presents the design, implementation, and validation of a real-time monitoring framework based on the Internet of Things (IoT) and cloud computing to enhance the thermal performance of evacuated tube solar water heaters (ETSWHs). A commercial system and a custom-built prototype were instrumented with Industry 4.0 technologies, including platinum resistance temperature detectors (PT100), solar irradiance and wind speed sensors, a programmable logic controller (PLC), a SCADA interface, and a cloud-connected IoT gateway. Data were processed locally and transmitted to cloud storage for continuous analysis and visualization via a mobile application. Experimental results demonstrated the prototype’s superior thermal energy storage capacity −47.4 vs. 36.2 MJ for the commercial system, representing a 31%—achieved through the novel integration of Industry 4.0 architecture with an optimized collector design. This improvement is attributed to optimized geometric design parameters, including a reduced tilt angle, increased inter-tube spacing, and the incorporation of an aluminum reflective surface. These modifications collectively enhanced solar heat absorption and reduced optical losses. The framework effectively identified thermal stratification, monitored environmental effects on heat transfer, and enabled real-time system diagnostics. By integrating automation, IoT, and cloud computing, the proposed architecture establishes a scalable and replicable model for the intelligent management of solar thermal systems, facilitating predictive maintenance and future integration with artificial intelligence for performance forecasting. This work provides a practical, data-driven approach to digitizing and optimizing heat transfer systems, promoting more efficient and sustainable solar thermal energy applications.

In this paper, the authors examine various slip effects on the magnetic field and thermal radiative impacts on the flow, mass and heat transfer of a Jeffrey nanofluid over a 2-dimensional inclined stretching sheet by a porous media. The offered work is modelled to be in the form of a combination of coupled highly nonlinear partial differential equations in dimensional contexts. Governing equations were obtained, dimensionless parameters were defined in terms of similarity parameters, and the solutions were obtained by the Homotopy Analysis Method (HAM). The analysis is significant as the effects of viscosity are identified and the important parameters are to be determined that could eventually control a type of flow behaviour, especially in promoting the flow and inhibiting flow of velocity, temperature, and concentrations. The findings show that such an increase in the magnetic parameter decreases the velocity profile by approximately 15% due to more Lorentz forces, and thermal radiation increases the temperature profile by up to 25%, therefore, enhancing the rate of heat transfer. The process of Brownian motion and thermophoresis increases the depth of the thermal boundary layer by 10–20 percent and reduces in concentration profiles by 12 percent when the Brownian motion parameter increases. A velocity slip parameter lowers the velocity field by about 18 percent, and a parameter of permeability lowers the momentum of flow by another 10 percent. The HAM solutions show very high accuracy levels, having an order of convergence at level 15 and error margins are well below 0.01 percent compared to the earlier studies. All these findings can provide profound knowledge in improving heat transmission in non-Newtonian fluid systems and can be used in biomedical engineering, thermal insulation, and industrial processes such as polymer extrusion and cooling technology. Principles of heat and mass transfer give us the crucial foundation on which to study the behavior of heat and material flows in other engineering and scientific disciplines. Such principles apply to various fields of study, including the following engineering fields: mechanical, chemical, aerospace, civil, and environmental.

A wide range of technological and industrial domains, including heating processors, electrical systems, mechanical systems, and others, are facing issues as a result of the recent developments in heat transmission. Nanofluids are a novel type of heat transfer fluid that has the potential to provide solutions that will improve energy transfer. The current study investigates the effect of a magnetic field on the two-dimensional flow of Williamson nanofluid over an exponentially inclined stretched sheet. This investigation takes into account the presence of multi-slip effects. We also consider the influence of viscous dissipation, thermal radiation, chemical reactions, and suction on the fluid’s velocity. We convert the nonlinear governing partial differential equations (PDEs) of the fluid flow problem into dimensionless ordinary differential equations (ODEs) through the utilization of similarity variables. We then use the homotopy analysis method (HAM) to numerically solve the resulting ordinary differential equations (ODEs). We demonstrate the effects of numerous elements on a variety of profiles through graphical and tabular representations. We observe a drop in the velocity profile whenever we increase either the magnetic number or the suction parameter. Higher values of the Williamson parameter lead to an increase in the thermal profile, while the momentum of the flow displays a trend in the opposite direction. The potential applications of this unique model include chemical and biomolecule detection, environmental cleansing, and the initiation of radiation-induced chemical processes like polymerization, sterilization, and chemical synthesis.

The present study investigates the non-isothermal flow and energy distribution through a loosely bent rectangular duct using a spectral-based numerical approach over a wide range of the Dean number $0<Dn\le 3000$. Unlike previous research, this work offers novel insights by conducting a grid-point-specific velocity analysis and identifying new bifurcation structures. The study reveals how centrifugal and buoyancy forces interact to produce steady, periodic, and chaotic flow regimes significantly influencing heat transfer performance. The Newton-Raphson method is employed to explore four asymmetric steady branches, with vortex solutions ranging from 2- to 12 vortices. Unsteady flow characteristics are analyzed exquisitely by performing time-advancement of the solutions and the flow regimes are shown as a percentage of total flow with longitudinal vortex generation. Axial flow, secondary flow, and temperature profiles have been depicted in accordance with Dn to wander the flow pattern, and it is predicted that the time-dependent flow (TDF) consists of asymmetric 2- to 10-vortex solutions. The significant findings of this study include the axial displacement of the circulations due to the influence of the time-varying temperature dispersal applied along the wall. Chaotic flows, which dominate the higher Dean number range, are shown to enhance heat convection due to increased fluid mixing. A detailed comparison with prior research demonstrates the advantages of this approach, particularly in capturing complex non-linear behaviors. The findings of this study provide practical guidelines for optimizing duct designs to maximize heat transfer and suggest future research directions, such as using nanofluids or studying Magneto-hydrodynamics in the same configuration.