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An induced magnetic field is produced owing to an electric current flowing through the conductor. The induced magnetic field and the length of the conductor are in direct proportion. The current study examines the comparison of Yamada-Ota and Xue thermal conductivity models for a mixed convective hybrid nanoliquid flow through the permeable vertical channel influenced by an induced magnetic field. The projected model is supported by the combination of thermal radiation and heat generation and multiple slip conditions imposed on the walls. The Tiwari and Das model is adopted considering engine oil as a working liquid with immersed multiwalled and single-walled carbon nanotubes (CNTs) nanoparticles. The unique combination of strength, conductivity, and other properties make CNTs a promising material for an extensive variety of applications. These governing partial differential equations undergo conversion to ordinary differential equations via the similarity transformation and are then numerically processed with the bvp4c technique of the MATLAB program. The outcomes are deliberated logically via illustrations and tables. It is perceived that fluid velocity is compromised by strengthening the induced magnetic field. Nevertheless, an opposing trend is witnessed for the enhanced values of the Prandtl number. [ABSTRACT FROM AUTHOR]

AbstractIn the present investigation, the onset of Marangoni convection in the flow of self-rewetting fluid over a stretching disk has been discussed. The self-rewetting fluid is considered to be electrically conducting and the flow problem is discussed under the influence of an induced magnetic field. The fluid flow is mainly induced due to two different mechanisms: (i) onset of Marangoni convection due to presence of temperature gradient along the liquid-gas interface and (ii) induction of magnetic field due to presence of an external magnetic field, which modifies the original field. The governing partial differential equations are written, following Navier-stokes equations and Prandtl boundary layer equation. With the use of similarity transformations, the governing equations are turned into a system of ordinary differential equations. Nonlinear systems of ordinary differential equations are solved by the bvp4c technique. The reciprocal of the magnetic Prandtl number diminishes the induced magnetic profile. [ABSTRACT FROM AUTHOR]

This study encapsulated the research methodology utilized in the flow behaviors of Williamson nanofluid and analyzed the associated mass heat transfer. The study concentrated on examining the magnetohydrodynamic behavior of nanofluids in the presence of heat generation effects and the inclusion of dissipative energy on a vertical nonlinear stretching surface submerged within a Darcy porous medium. The rationale for including variable viscosity and variable conductivity in this research was to precisely evaluate the mechanisms of heat and mass transfer, particularly with regard to the fluctuations in fluid properties. The objective was to enhance the understanding of how these varying properties impact the overall heat and mass transfer processes. The initial formulation of the phenomenon, initially presented as partial differential equations, was transformed into ordinary differential equations by employing appropriate dimensionless variables. The ultimate streamlined version of the model was then numerically solved utilizing the shooting method. By employing the numerical shooting method, we portrayed nanofluid patterns in velocity, temperature, and concentration fields, alongside essential parameters such as skin friction coefficient, Sherwood number, and Nusselt number. The significant key findings highlighted that both the porous parameter and the magnetic number increasingly affected temperature and concentration distributions. Additionally, increasing the thermophoresis parameter resulted in higher concentration and corresponding temperature levels. Graphical presentation and physical explanations were used for analysis, and the study's outcomes were compared to existing literature, affirming a strong agreement that validated the solutions. [ABSTRACT FROM AUTHOR]

In this paper, the investigation centered on examining a Maxwell fluid’s convective double diffusive flow carefully considers factors such as chemical reactions, radiation, and the presence of a permeable moving flat plate. Additionally, the study encompassed the effects of heat generation and magnetohydrodynamics (MHD). The governing equations, initially expressed as partial differential equations, were converted into ordinary differential equations using a similarity transformation technique to facilitate the analysis. The computational power of MATLAB’s BVP4C software was harnessed to solve this resultant system of ODEs efficiently. The outcomes of this investigation were presented in the form of graphical representations that vividly depicted the behavior of the flow field, energy conservation, and concentration profiles under various parameter combinations. The research findings were thoughtfully summarized in a table, offering a comprehensive overview of temperature, velocity, and mass profiles across various parameters. These parameters included the Deborah number, chemical reaction rate, Eckert number, Lewis number, Prandtl number, porosity parameter, and MHD parameter. A notable discovery emerging from this study was the inverse relationship observed between nondimensional concentration contours and the magnitude of the chemical reaction rate. Simultaneously, it was observed that higher values of the Maxwell fluid led to a rise in the thickness of the temperature boundary layer. These findings offer valuable insights into the intricate interplay of physical and chemical phenomena in convective flows involving complex fluid properties and boundary conditions. The temperature outline diminishes as the heat generation rate increases, while the concentration profile declines with an elevation in the chemical reaction rate. [ABSTRACT FROM AUTHOR]

[Objectives]To solve the current problems of large amount of agricultural waste, low resource utilization rate, and low temperature and insufficient CO2 for production of facility vegetables in cold winter areas in China, a shed type biomass fermentation device was designed. [Methods]This equipment included fermentation shed body(6 m long, 5 m wide, 2.8 m ridge height), forced heat exchange device and indoor heating pipeline in three parts. Using corn straw and sheep manure as raw materials for layered pile fermentation, the thermal performance of the fermentation unit brew, the impact on the thermal environment, gas environment and production of the facility greenhouse, and the economic benefits were explored. [Results]The temperature of the pile in the fermentation unit was above 50 ℃ for a total of 65 d, and the heat production efficiency reached 74.94%. The temperatures were more than 1.04 ℃ higher compared with the control greenhouse. The global warming potential(GWP)index decreased 96.98% through the gas filtration device and CO2 recovery system during the composting process. The CO2 concentration increased 2 270.58 mg·m-3. The soluble protein and vitamin C contents of tomatoes in the heated area were 24.6% and 29.2% higher than those in the control area respectively, and the lycopene was 71.3% higher than that in the control area. The operation of the biofermentation unit increased the field per plant by 5.99% and increased income by 8 712 yuan. [Conclusions]The application of shed-body biomass brew heaters in cold regions could provide heat and CO2 required for crop growth in facility greenhouses. [ABSTRACT FROM AUTHOR]

The investigation focused on a Maxwell fluid's convective double diffusive flow, considering the influences of chemical reaction radiation on a permeable moving horizontal plate. Factors like heat generation, Newtonian heating conditions, and the effect of MHD were also included in this study. The governing equations, presented as partial differential equations, are then transformed into ordinary differential equations (ODEs) via similarity transformation approach. MATLAB's built-in software, BVP4C, was considered to solve the resulting system of ODEs. The obtained solutions were presented as graphical representations illustrating the flow field, energy conservation, and concentration behaviours for different parameter combinations. The targeted parameter here is to be taken as a Newtonian heating condition on the boundary, so the critical discovery from this study is the increase in nondimensional temperature contour and Nusselt number profile as the Newtonian heating effect value increased. The Sherwood number profile rose as the chemical reaction effect value increased. We have rigorously validated our work by comparing it to existing research, and the results have demonstrated a remarkably high degree of alignment. Consequently, we can confidently assert that our code is accurate and effectively aligned with this field's existing body of knowledge. This validation process reinforces the reliability and validity of our work, underlining its robustness and correctness. [ABSTRACT FROM AUTHOR]

The investigation endorsed the convective flow of Carreau nanofluid over a stretched surface in presence of entropy generation optimization. The novel dynamic of viscous dissipation is utilized to analyze the thermal mechanism of magnetized flow. The convective boundary assumptions are directed in order to examine the heat and mass transportation of nanofluid. The thermal concept of thermophoresis and Brownian movements has been re-called with the help of Buongiorno model. The problem formulated in dimensionless form is solved by NDSolve MATHEMATICA. The graphical analysis for parameters governed by the problem is performed with physical applications. The affiliation of entropy generation and Bejan number for different parameters is inspected in detail. The numerical data for illustrating skin friction, heat and mass transfer rate is also reported. The motion of the fluid is highest for the viscosity ratio parameter. The temperature of the fluid rises via thermal Biot number. Entropy generation rises for greater Brinkman number and diffusion parameter. [ABSTRACT FROM AUTHOR]

Purpose: To assess the changes in intrapulpal temperature between electric high‐speed handpieces of different coolant functions ('Water Jet' and 'Water Spray'), coolant port designs (1‐ and 4‐port), suction use, and bur and tooth types using an experimental in vitro setup. Materials and methods: Forty‐four extracted anterior and posterior teeth were collected. A total of 18 groove cuts (n = 18/coolant port spray design, bur and tooth type group) and 12 groove cuts (n = 12/tooth type and suction use) were completed, with a total of 264 groove cuts. Real‐time temperature and duration were recorded at 1‐s intervals throughout the preparation process using a thermocouple and digital data logger setup (GFX Data Logger Series and EL USB‐TC; Lascar Electronics Inc., USA), and the data retrieved using EasyLog Software (EasyLog USB; Lascar Electronics Inc., USA). Statistical analysis was performed (SPSS V.27) for the change in temperature using the analysis of variance and post hoc analysis. Results: The majority of the specimen cuts, regardless of tooth (anterior or posterior) and bur (diamond or carbide) types, handpiece coolant port design, and suction use showed an overall decreasing trend in intrapulpal temperature. No cuts caused a mean temperature change that reached the critical temperature of 42.5°C or resulted in an overall increase in intrapulpal temperature when the 60‐s duration was completed. Conclusions: The tested electric handpieces efficiently reduced intrapulpal temperature, with the majority displaying a decreasing trend. A greater decrease in intrapulpal temperature was observed in canines compared to premolars; carbide burs compared to diamond; and with no suction preparations compared to when suction was used. [ABSTRACT FROM AUTHOR]

Inertia friction welding (IFW) is a robust joining technique, particularly for hybrid structures composed of similar or dissimilar alloys. The highly transient thermal responses during friction heating produce variations in heat generation and temperature distribution, which are crucial for designing and controlling the IFW process. This study establishes a finite element (FE) model of the IFW process for dissimilar superalloys and investigates the transition of the interfacial friction regime and its impact on the transient thermal responses. The in-process state variables, including the frictional stress and heat flux, along with their spatial distributions at the welding interface, are obtained through FE simulations. The predicted results indicate that the transient transition of the friction regime produces two Coulomb friction zones accompanied by a shear friction zone. To capture the transient evolution of the friction regime, a novel phenomenological formula is developed. This model accurately predicts the shrinkage and disappearance of the two Coulomb friction zones and the enhancement of the shear friction zone from the initial 0.42 R0–0.87 R0 (where R0 is the workpiece radius) to the entire interface during the IFW process. The variations in interfacial heat flux, frictional stress, and temperature caused by the transition of the friction regime are comprehensively analyzed. Our results reveal that the transition from the Coulomb friction regime to shear friction regime at the interface is beneficial for temperature homogenization at the welding interface. The FE simulation results are validated against published experimental measurements, which confirms the accuracy and reliability of the FE model.

This study encapsulated the research methodology utilized in the flow behaviors of Williamson nanofluid and analyzed the associated mass heat transfer. The study concentrated on examining the magnetohydrodynamic behavior of nanofluids in the presence of heat generation effects and the inclusion of dissipative energy on a vertical nonlinear stretching surface submerged within a Darcy porous medium. The rationale for including variable viscosity and variable conductivity in this research was to precisely evaluate the mechanisms of heat and mass transfer, particularly with regard to the fluctuations in fluid properties. The objective was to enhance the understanding of how these varying properties impact the overall heat and mass transfer processes. The initial formulation of the phenomenon, initially presented as partial differential equations, was transformed into ordinary differential equations by employing appropriate dimensionless variables. The ultimate streamlined version of the model was then numerically solved utilizing the shooting method. By employing the numerical shooting method, we portrayed nanofluid patterns in velocity, temperature, and concentration fields, alongside essential parameters such as skin friction coefficient, Sherwood number, and Nusselt number. The significant key findings highlighted that both the porous parameter and the magnetic number increasingly affected temperature and concentration distributions. Additionally, increasing the thermophoresis parameter resulted in higher concentration and corresponding temperature levels. Graphical presentation and physical explanations were used for analysis, and the study's outcomes were compared to existing literature, affirming a strong agreement that validated the solutions.

The utilization of a ternary hybrid nanofluid, a recent development in the realm of nanofluids, can result in improved heat transfer. In the ongoing study, a ternary hybrid nanofluid flow is utilized, and it is carried out atop a porous spinning disc, which is exposed to a magnetic field, heat generation, thermal radiation, and Casson fluid. In this study, Blood/Water are taken as base fluids and (Ag–Au–Al2O3) are considered as a ternary hybrid nanoparticle. Nanoparticles made of gold and silver are put to use in a vast number of industries and fields, including nanotechnology and medicine. As a result of surface effects and quantum effects, these precious metals exhibit unique features in nanoform that play a vital role in with optical, magnetic, chemical, and mechanical behavior. Al2O3 unique optical, physical and biochemical qualities make it worthwhile for numerous uses, including nanophotonic, catalysis and the fabrication of high-energy composites. A set of relevant similarity transformations is used to generate non-dimensional forms of controlling paired nonlinear Partial Differential Equations (PDEs). MATLAB is used to perform a numerical solution with ODE45. In addition, the velocity outline decreases, and the temperature profile increases slightly before decreasing over a revolving disk when the values of magnetic parameters are increased. The distribution and radiant heat components heat up as the level gets higher. Aim and objectives of the study: The aim of this study is to analyze the Comprehensive Scrutinization of Ternary hybrid and Casson flow in a conducting porous rotating disk with internal heating. The primary objective of this analysis is to increase awareness of the impending energy crisis among those working in the industrial and technological sectors. Ternary nanoparticles (NPs) have a wide range of applications, which lends credence to the developed model. For example, Al2O3 can be used in a variety of ways that benefit society, it is used in water purification to remove water from the gas streams and extend people's lives. [ABSTRACT FROM AUTHOR]

This article is concerned with the boundary layer formations over a deforming plane heated surface in a viscoelastic fluid having temperature-dependent physical properties. Viscoelastic fluid obeys a well-accepted Jeffrey fluid model that characterizes both relaxation and retardation times phenomena. Mathematical modeling is performed by considering exponential variations in viscosity, thermal conductivity, relaxation time, and retardation time with temperature. Transport equations are formulated under the aforesaid assumption and are solved for self-similar solutions using a numerical scheme. Solutions are utilized to generate streamlines and isotherms in both Newtonian and viscoelastic fluids. The momentum and thermal layers are specifically scrutinized for various controlling parameters. Illustrative results are included reflecting the consequences of variable physical properties on the induced viscoelastic fluid motion and accompanying heat transfer. In addition, skin friction factor for Jeffrey fluid with variable properties is evaluated and described. [ABSTRACT FROM AUTHOR]

In this paper, the Levenberg-Marquardt backpropagation scheme is used to develop a neural network model for the examination of the fluid flow on a magnetized flat surface with slip boundaries. The tangent hyperbolic fluid is considered along with heat generation, velocity, and thermal slip effects at the surface. The problem is modelled in terms of a non-linear differential system and Lie symmetry is used to get the scaling group of transformation. The order reduction of differential equations is done by using Lie transformation. The reduced system is solved by the shooting method. The surface quantity, namely skin friction, is evaluated at the surface for the absence and presence of an externally applied magnetic field. A total of 88 sample values are estimated for developing an artificial neural network model to predict skin friction coefficient (SFC). Weissenberg number, magnetic field parameter, and power law index are considered three inputs in the first layer, while 10 neurons are taken in the hidden layer. 62 (70%), 13 (15%), and 13 (15%) samples are used for training, validation, and testing, respectively. The Levenberg-Marquardt backpropagation is used to train the network by entertaining the random 62 sample values. Both mean square error and regression analysis are used to check the performance of the developed neural networking model. The SFC is noticed to be high at a magnetized surface for power law index and Weissenberg number.

AbstractEffects of heat generation, chemical reaction and activation energy on Marangoni flow, heat and mass transfer over a circular porous surface are investigated. The problem has been formulated in the form of the nonlinear system of PDEs, which are changed to the dimensionless set of ODEs using the similarity replacement. The problem is solved numerically by a method named Legendre–Galerkin. The influences of the different parameters on the velocity, temperature and concentration are discussed and analysed. The local skin friction, local Nusselt number and local Sherwood number are also computed and investigated for different embedded parameters in the problem statements.

AbstractIn this article, the behavior of the truncated conical shell subjected to thermomechanical loading in their inner and outer layers with internal heat generation source is investigated. The displacement field obeys kinematic of the first order shear deformation theory and the first-order temperature theory is used. Two-dimensional temperature analysis has been performed along the thickness and axis of the shell, which can be defined under various loading and thermomechanical boundary conditions. The set of governing equations is a system of differential equations with variable coefficients which are solved by using the analytical matched asymptotic expansion of the perturbations technique. The mentioned solution has little computational cost, therefore can be used well in parametric studies for optimization. It was shown, axial displacement is somehow independent of the radial axis and its maximum value occurs near the upper boundary. The conical shell has expanded in the radial direction. Also the maximum temperature happens approximately in the middle of the length of the conical shell. The parametric study showed, with the increase heat flux in the outer layer thereby expanding the area of heat application which would let more heat in than out. Also it was found, controlling the lifetime of the structure is the result of directing the cone angle. The results obtained from the analytical solution were compared with the Finite Element Method (FEM) analysis and the results of similar related articles, only to show a good agreement. [ABSTRACT FROM AUTHOR]

Build simply – does a mechanical ventilation system in residential buildings save costs and energy? In Bad Aibling, three residential buildings were built in 2020 as research houses made of masonry, wood, and concrete, respectively. The complexity was reduced through simple construction and reduced building services: no mechanical ventilation; only presence‐controlled exhaust air from the interior bathroom was installed. The study addresses the question of whether it would have been better to install a mechanical ventilation system in the rooms. Four variants are compared: scenario A: natural (window) ventilation + bathroom exhaust air presence‐controlled (as built); scenario B: natural (window) ventilation + bathroom exhaust air presence‐controlled with basic ventilation; scenario C: single room heat recovery ventilator (SRHRV); scenario D: centralized ventilation (MVHR) (apartment unit) with heat recovery. The environmental impact and the costs of the respective ventilation systems caused by purchase, maintenance and operating energy over the life cycle were considered. Scenario A (as built) performs best in costs and global warming potential. Scenario C and D in particular would have to achieve high savings in heat demand in order to compensate for the negative environmental impact of the ventilation systems. In comparative measurements in practice, no corresponding savings effects could be determined. Mechanical ventilation is not suitable for improving the environmental impact or life cycle costs. [ABSTRACT FROM AUTHOR]

This work examines the Stefan blowing effect on the magnetized stagnation point flow of Prandtl–Eyring nanoliquid along a nonlinear elongating surface under the influence of numerous slips. In this study, the impressions of internal heat sources, nonlinearly varying radiation, activation energy with binary chemical reactions, viscous dissipation, and Joule dissipation are taken into account. The thermal flux associated with thermal radiation is computed using Rosseland's approximation for an optically thick environment. The controlling dimensional mathematical equations are transformed into nondimensional representations using appropriate similarity transmissions. Numerical temperature, velocity, and concentration solutions are obtained using a shooting method based on secant iteration and the Runge–Kutta–Fehlberg method. Using tabular and graphical displays of numerical data, the physical effects of a number of relevant parameters on the nanoliquid temperature, velocity, and concentration are examined. By contrasting the current results with information that has already been published for a few limiting circumstances, the validity of the acquired results is demonstrated. The effects of physical features on the local surface drag coefficient, rates of mass and heat transfer are demonstrated using numerical data shown in tabular form. For increasing values of the Stefan blowing parameter, fluid velocity decreased. The fluid temperature tends to rise as a result of thermal radiation. [ABSTRACT FROM AUTHOR]

In this paper, the Levenberg-Marquardt backpropagation scheme is used to develop a neural network model for the examination of the fluid flow on a magnetized flat surface with slip boundaries. The tangent hyperbolic fluid is considered along with heat generation, velocity, and thermal slip effects at the surface. The problem is modelled in terms of a non-linear differential system and Lie symmetry is used to get the scaling group of transformation. The order reduction of differential equations is done by using Lie transformation. The reduced system is solved by the shooting method. The surface quantity, namely skin friction, is evaluated at the surface for the absence and presence of an externally applied magnetic field. A total of 88 sample values are estimated for developing an artificial neural network model to predict skin friction coefficient (SFC). Weissenberg number, magnetic field parameter, and power law index are considered three inputs in the first layer, while 10 neurons are taken in the hidden layer. 62 (70%), 13 (15%), and 13 (15%) samples are used for training, validation, and testing, respectively. The Levenberg-Marquardt backpropagation is used to train the network by entertaining the random 62 sample values. Both mean square error and regression analysis are used to check the performance of the developed neural networking model. The SFC is noticed to be high at a magnetized surface for power law index and Weissenberg number. [ABSTRACT FROM AUTHOR]

The analysis of non-Newtonian fluid flow over an oscillating surface often involves numerical simulations and experimental investigations. Computational fluid dynamics method including finite difference or finite element techniques can be used to crack the governing equations of the fluid flow. In this work, we used the Crank–Nicolson numerical technique to analyze the numerical behavior of unsteady boundary layer flow of Casson fluid with natural convection past an oscillating vertical plate. The temperature-dependent viscosity is assumed for the flow analysis. The impact of chemical reaction and heat generation coefficient is used to examine the mass and heat transferal rates. The investigation of non-Newtonian fluid flow over an oscillating surface is crucial for a wide range of industrial, biomedical, and scientific applications. The governing model of equations occurs in the form of nondimensional PDEs and then we use the dimensionless variables in order to achieve the dimensional PDEs. These equations are numerically solved by using the Crank–Nicolson technique. The Crank–Nicolson scheme is used because it has the ability to provide accurate and stable solutions and make it a valuable numerical technique in various scientific and engineering disciplines. The findings indicate the significance of numerous parameters on the mass, velocity and energy regions. The numerical outcomes of skin friction are observed due to fluid parameter, viscosity parameter, Grashof numbers of heat and solutal rates. [ABSTRACT FROM AUTHOR]

Friction stir welding (FSW), a solid‐state joining method, is an innovative technique widely employed in the welding of thermoplastics, with broad application areas such as the automotive and aerospace industries. Due to its inherent advantages, including ease of processing, biodegradability, and printability, polylactic acid (PLA) and its derivatives are notably the most commonly used polymers in 3D printing. The limited print area of 3D printers necessitates post‐production joining processes. In this study, the weldability of plates obtained using PLA Wood filament through the FSW is evaluated. For this purpose, different pin geometries (triangle, square, and screw), feed rates (20, 40, and 60 mm/min), and tool rotation speeds (1250, 1750, and 2250 rpm) are employed. Visual inspections are conducted to determine the effects of process parameters on weld quality and to identify defects in the weld region. Temperature values are measured to investigate the influence of heat generated during the FSW process. Furthermore, after determining the highest weld strengths achieved for each pin geometry, the weldability of PLA Wood material with PLA‐CF and PLA Plus materials is investigated using these parameters. The results indicate that the highest weld quality for joining PLA Wood plates is achieved using the square pin geometry, 20 mm/min feed rate, and 1750 rpm with an efficiency of 74.5%. When welding PLA Wood with PLA‐CF and PLA Plus, high weld strengths are obtained using the same process parameters (square pin, 20 mm/min, and 1750 rpm). Highlights: Friction stir welding process of 3D printed PLA Wood material.Friction stir welding process of dissimilar materials pairs.Effect of welding parameters on weld strength and hardness.Identifying the fracture surface images occurring in parts after friction stir welding.Examination of temperature generation during friction stir welding. [ABSTRACT FROM AUTHOR]

Due to its remarkable thermodynamic development in various engineering sciences, the dispersion of nanostructures in classical base liquids is receiving greater attention from researchers and scientists. In light of the aforementioned inspirations, the suggested research is associated with using a water-based ternary-hybrid nanofluid that contains three unique nanostructures, silicon dioxide, titanium dioxide and aluminum oxide to optimize the heating process in science and engineering. In this situation, the influence of a chemically reactive magneto-hydrodynamics (MHD) Darcy–Forchheimer ternary hybrid composites transport involving nonlinear radiation across an exponentially permeable stretched surface is highlighted with the model's physical initial and boundary constraints. The simulation of the heat expression also includes the impacts of nonlinear thermal radiations, energy supply, energy dissipation and magnetic force. Furthermore, the interpretation of Buongiorno's theory involves spontaneous and thermophoresis diffusions. Entropy analysis is explained using the second law of thermodynamics. We converted the model framework for fluid movement, energy and mass transfer (together with ternary hybrid nanofluid characteristics) into self-similar nondimensional differential equations, that were then further analytically evaluated by using the homotopy asymptotic method (HAM) technique via Mathematica software. The acquired results are illustrated numerically and graphically to study the behavior of fluid flow, heat, concentration distribution, drag force, rate of heat and mass transfer for various emergent components to gain scientific comprehension. With the growing values of magnetic, porosity and Forchheimer number, the nature of the velocity profile goes down. [ABSTRACT FROM AUTHOR]

Background: Dental implants can cause complications, including the loosening of the abutment screw or fracture. However, there is no standardized technique for removing broken abutment screws. This necessitates further research. Objective: This study aimed to measure heat generation during screw removal to better understand its implications for dental implant procedures. Material and methods: The experimental setup involved using synthetic bone blocks and titanium implants. An ultrasonically operated instrument tip was utilized for screw removal. Infrared thermometry was employed for accurate temperature measurement, considering factors such as emissivity and distance. Statistical analysis using linear regression and ANOVA was conducted. Results: The findings revealed an initial rapid temperature increase during the removal process, followed by a gradual decrease. The regression model demonstrated a strong correlation between time and temperature, indicating the heat generation pattern. Conclusion: Heat generation during screw removal poses risks such as tissue damage and integration issues. Clinicians should minimize heat risks through an intermittent approach. The lack of a standardized technique requires further research and caution. Understanding the generated heat optimizes implant procedures. [ABSTRACT FROM AUTHOR]

We analyze and quantify the amount of heat generated by a nanoparticle, injected in a background medium, while excited by incident electromagnetic waves. These nanoparticles are dispersive with electric permittivity following the Lorentz model. The purpose is to determine the quantity of heat generated extremely close to the nanoparticle (at a distance proportional to the radius of the nanoparticle). This study extends our previous results, derived in the 2D TM and TE regimes, to the full Maxwell system. We show that by exciting the medium with incident frequencies close to the plasmonic or Dielectric resonant frequencies, we can generate any desired amount of heat close to the injected nanoparticle while the amount of heat decreases away from it. These results offer a wide range of potential applications in the areas of photo-thermal therapy, drug delivery, and material science, to cite a few. To do so, we employ time-domain integral equations and asymptotic analysis techniques to study the corresponding mathematical model for heat generation. This model is given by the heat equation where the body source term comes from the modulus of the electric field generated by the used incident electromagnetic field. Therefore, we first analyze the dominant term of this electric field by studying the full Maxwell scattering problem in the presence of plasmonic or all-dielectric nanoparticles. As a second step, we analyze the propagation of this dominant electric field in the estimation of the heat potential. For both the electromagnetic and parabolic models, the presence of the nanoparticles is translated into the appearance of large scales in the contrasts for the heat-conductivity (for the parabolic model) and the permittivity (for the full Maxwell system) between the nanoparticle and its surroundings. [ABSTRACT FROM AUTHOR]

The thermal behavior of flooded lead–acid batteries with different distances between their electrodes, in which there takes place a temperature rise, was investigated at different rates of charging and discharging of these batteries with the use of the PIV method. It was established that, in the case of small rates of charging and discharging of such a battery, a decrease in the distance between its electrodes leads to a decrease in the temperature rise and in the heat generation in it, while, in the case where these rates are large, the opposite effects take place. [ABSTRACT FROM AUTHOR]

This study investigates the influence of periodic heat flux and viscous dissipation on magnetohydrodynamic (MHD) flow through a vertical channel with heat generation. A theoretical approach is employed. The channel is exposed to a perpendicular magnetic field, while one side experiences a periodic heat flow, and the other side undergoes a periodic temperature variation. Numerical solutions for the governing partial differential equations are obtained using a finite difference approach, complemented by an eigenfunction expansion method for analytical solutions. Visualizations and discussions illustrate how different variables affect the flow velocity and temperature fields. This offers comprehensive insights into MHD flow behavior and its interactions with the magnetic field, heat flux, viscous dissipation, and heat generation. The findings hold significance for engineering applications concerning fluid dynamics and heat transfer, offering valuable knowledge in this field. The study concludes that the transient velocity and temperature profiles exhibit periodic patterns under periodic heat flow conditions. A temperature reduction is observed with an increase in the wall temperature phase angle. In contrast, an increase in the heat flux phase angle values raises the temperature values. [ABSTRACT FROM AUTHOR]

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Efficiency of the battery pack largely depends on the resistive losses and heat generation between the interconnections of the battery cells. Grouping of battery cells usually is done in different ways in industries. However, losses vary depending on applications or states of electric vehicle (EV). Therefore, it is necessary to determine the efficiency and heat generation in battery cells as well as battery packs. In practical situations, some battery cells are charged rapidly in comparison to other battery cells. On the other hand, when an EV is in running condition some battery cells are discharged rapidly. As a results battery pack cannot provide better efficiency and its life span is reduced. As an alternative option the inter-cell connection of battery package is needed to reconfigure in an optimized way. In this paper firstly, a battery pack with switches is modeled and then efficiency and temperature variation with respect to time are determined. Then, an experimental setup is investigated to measure the efficiency and temperature rise with respect to time. Results, explained in the paper, demonstrate that battery pack with switches increases the efficiency if it is measured after switching (97–98 %), while temperature increases from 25 °C to 50 °C for different C-rates. [ABSTRACT FROM AUTHOR]

The nanofluids extensively contribute to cope the new heat transport challenges facing by the engineering systems and industries including paint, ceramics, chemical, aerodynamics, electronics, and medical sciences, etc. Thus, the innovations in new nanoliquid models can be disregarded in light of broad applications spectrum. Therefore, the current work concerns with the thermal process of hybrid nanoliquid by adding the important physical phenomenon. The flow of bionanofluid is taken inside a uniform expanding/contracting channel. To increase the model novelty, the significant influence of Lorentz forces, porous media, and heating source is added in the problem formulation. The resultant bionanofluid model is then analyzed via VIM (variational iteration method) and provided a deep discussion. It is inspected that unvarying expansion/contraction in the range of α = 1.0 , 2.0 , 3.0 , 4.0 and α = - 1.0 , - 2.0 , - 3.0 , - 4.0 , the bionanofluid attained maximum velocity about the central portion and in rest of the part it declines. However, due to increased viscosity of hybrid nanofluid, it reduced rapidly than conventional nanofluid. By increasing the permeability from 0.1 to 0.4, a rapid decrease in the fluid movement is observed. Further, the heat transmission progress reduced against the porous medium and Lorentz forces. The heat generation effects boosted the heating performance of the hybrid nanofluid. Moreover, the skin friction and heat transport rate are also discussed. [ABSTRACT FROM AUTHOR]

• Effects of temperature and moisture content on MSW heat generation were studied. • Maximum heat generation occurred at an initial temperature of about 40 °C. • A simple formula for calculating heat generation by MSW degradation was proposed. Heat generation from degradation of organic matter in municipal solid waste (MSW) often leads to increased landfill temperature. However, it is difficult to measure environmental heat loss in laboratory and field tests; therefore, little research has been conducted to evaluate heat generation during waste degradation under different initial temperatures and moisture contents. In this study, tests were conducted to investigate the effects of initial temperature and moisture content on heat generation during waste degradation. A simple formula for calculating heat generation was proposed. Within 200 h, the waste temperature decreased by about 70%, and lower initial moisture contents were associated with greater temperature decreases. The smallest temperature decrease of 47% and the greatest heat generation occurred when the initial temperature was 40 °C. The initial moisture content increased from 30% to 60% and the heat generation increased from 5% to 36%. The heat generation per unit mass of organic matter during the aerobic and anaerobic stages were 19.44–23.77 and 0.27–0.50 MJ·kg−1, respectively, indicating that the proposed formula for calculation of heat generated from waste degradation was reasonable. The results presented herein provide theoretical support for the prediction of heat generation and the recycling of heat resources in MSW landfill sites. [ABSTRACT FROM AUTHOR]

In this work, a facile solvothermal synthesis of MnFe2O4 nanoparticles is followed by an easy and reproducible process to envelop the synthesized MnFe2O4 nanoparticles with iron oxide nanoparticles using ethanol and ethylene glycol as solvents. All prepared MnFe2O4 nanoparticles show a homogenous distribution of spherical particles with an average particle size between 12 and 16 nm. The encapsulation process of MnFe2O4 nanoparticles does not affect their homogenous distribution with a very thin layer of Fe3O4 on the shell structure. The magnetic properties showed a superparamagnetic character with enhanced magnetic properties of MnFe2O4@Fe3O4 compared to pure MnFe2O4, which has been verified by magnetization and electron spin resonance. The heating efficiency of the prepared samples was evaluated in terms of the specific loss power using the calorimetric method. The synthesized MnFe2O4 nanoparticles show a significantly high value of about 72 W/g, which got doubled in the core@shell structure and reached 140 W/g at 189 kHz and 10kA/m of the magnetic field. [ABSTRACT FROM AUTHOR]

The work-hardening and low thermal conductivity characteristics of SS304 had always been a challenge to machine it easily with better tool life and surface finish. The type of coolant, its temperature and surface coated inserts plays a pivotal role in machining the hard materials. A number of experiments were performed with a TiCN and tungsten carbide inserts in combination with soluble/synthetic coolant at ambient temperature and at 0oC TiCN-coated cemented carbide insert with synthetic coolant at 0°C is recommended for machining as per the results obtained through this research work. It was found that TiCN-coated inserts used for machining SS304 with synthetic coolant at 0°C provide better tool life, less tool wear, improved surface finish and low heat generation. The tool life was enhanced approximately by 75%, 20% reduction in maximum temperature generation and 50% improvement in surface finish of workpiece. [ABSTRACT FROM AUTHOR]

The main theme of this research is to deliberate the irreversibility aspects of spinning nanofluid (PEG-H2O / ZrO2) and hybrid (PEG-H2O / ZrO2–MgO) nanofluid towards a movable sheet. Here a mixture of polyethylene glycol and water is utilised as a continuous phase fluid. Two different nanoparticles are considered, i.e., zirconium dioxide (ZrO2) and magnesium oxide (MgO). The heat transfer behaviour is examined and modelled subject to viscous dissipation, heat source and heat flux. Furthermore, the entropy generation problem is addressed by the second law of thermodynamics. Nonlinear dimensionless differential systems are developed by suitable variables. The given dimensionless systems are solved using numerical techniques (ND-solve method). Effects of influential variables on fluid flow, temperature, Bejan number and entropy rate for both PEG-H2O / ZrO2 and PEG-H2O / ZrO2–MgO fluids are graphically examined. A higher approximation of volume fractions rises the velocity profile, while reverse impact is seen for the Bejan number. An increment in rotation variable corresponds to increased velocity. A similar scenario is seen for the thermal field and entropy rate through the radiation effect. An opposite impact is seen for the Bejan number and entropy rate through the Brinkman number. An augmentation in temperature is seen for the Eckert number. Furthermore, we noticed that heat transport in a hybrid nanofluid (PEG-H2O / ZrO2–MgO) is higher than that for the nanofluid (PEG-H2O / ZrO2). [ABSTRACT FROM AUTHOR]

This present study involves examining the nature of 3D rotational MHD nanofluid flow through a stretching sheet. Alumina Al 2 O 3 –ethylene glycol C 2 H 6 O 2 -based nanofluid is considered in this investigation. A normal magnetic field acts on the sheet. Radiative thermal boundary condition with slip velocity has been considered. Suitable similarity transformation is used to derive a system of ordinary differential equations. The spectral quasilinearisation method (SQLM) is applied to solve this system. For curiosity, the skin friction coefficient and Nusselt number have been calculated. Due to effective heat generation and heat radiation, a significant temperature difference is produced. Besides, the impact of the variation in the volume fraction of nanoparticles is remarkable. The influence of key parameters has also been shown graphically. The graphical representation shows that the magnetic parameter declines in the radial velocity component, while the layout of the tangential component of velocity enhances in the form of a parabola with an enhancement of the magnetic parameter. Temperature layout is enhanced with the increasing values of the magnetic parameter, nanoparticle volume fraction, temperature ratio parameter, radiation parameter and Biot number. The generation of entropy enhances with the increase in the magnetic parameter, Brinkman number and Reynolds number, while nanoparticle volume fraction and temperature difference parameters decrease the entropy generation. For the engineering interest, the skin friction coefficient along the x-axis, y-axis and the local Nusselt number have also been calculated. The impacts of pertinent parameters on the skin friction coefficient along the x-axis, y-axis and the local Nusselt number are scrutinised numerically. We have compared our current result with the available studies for special cases ϕ = 0 , M = 0 and found that the results are in good agreement. [ABSTRACT FROM AUTHOR]

Bladed mixers are commonly used for processing granular materials, requiring significant mechanical energy for optimal blending. During this process, heat is generated due to dissipated mechanical energy within the granular medium. However, our understanding of heat generation mechanisms without external thermal loads is limited. This article investigates heat generation by monitoring temperature changes in granular beds mixed using an overhead stirrer. First‐order kinetic equations are employed to extrapolate experimental data to a thermal equilibrium where heat generation and loss rates are balanced. Lead, steel, and glass particles are utilized under different operating conditions. Notably, metallic particles exhibit faster heating due to their lower heat capacity. Increasing rotation speed, fill ratio, and particle size result in greater temperature rises. Additionally, flat blades generate more heat compared to tilted blades. Through dimensional analysis, the experimental data are collapsed into linear curves that correlate system power consumption and granular bed temperature with operating conditions. [ABSTRACT FROM AUTHOR]

The objective of the current article is to probe entropy generation in EMHD thermal transports of hybrid nanofluid which has indeed been enhanced by better thermal transfer to handle growing heat density of tiny and other technological operations. Non-Newtonian fluids like Casson and Williamson are encrypted for this present physical model and also in the blood, gold (Au) and silver (Ag) are hybridized to form an extremely diluted, homogeneous combination. The non-linear PDE system of equations are synthesized into an ordinary differential system via appropriate self-similarity variables, which are then computed by utilizing the homotopy perturbation technique. Visual representations are used to demonstrate the effects of various factors. With a few exceptions, the model's study results are pretty close to those found in the literature. For various profiles, with the influence of active parameters, the results are displayed graphically. This shows that when the parameters of magnetic, Casson and Williamson fluids are inclined, the radial and azimuthal velocity profiles decrease, sharply it attains contradiction phenomena to the increasing electric field inputs. Entropy production increases for magnetic fields and the Bejan number exhibits declination. The predictions are pertinent to the delivery of targeted nanoparticle drugs in hematology. [ABSTRACT FROM AUTHOR]

Effects of heat generation, chemical reaction and activation energy on Marangoni flow, heat and mass transfer over a circular porous surface are investigated. The problem has been formulated in the form of the nonlinear system of PDEs, which are changed to the dimensionless set of ODEs using the similarity replacement. The problem is solved numerically by a method named Legendre–Galerkin. The influences of the different parameters on the velocity, temperature and concentration are discussed and analysed. The local skin friction, local Nusselt number and local Sherwood number are also computed and investigated for different embedded parameters in the problem statements. [ABSTRACT FROM AUTHOR]

This paper presents an in-depth investigation of the creep behavior of a thick-walled cylinder subjected to thermomechanical loads with internal heat generation under various boundary conditions. The cylinder is subjected to internal pressure with the incoming heat flux in the inner layer and the outgoing heat flux from the outer layer accompanied by heat generation. The displacement field follows the kinematics of the first-order shear deformation theory (FSDT). Simultaneously, the temperature field is treated as two-dimensional, exhibiting variations both along the thickness and the length of the cylinder, with a linear temperature gradient across the cylinder's thickness. Using the energy method, the equilibrium equations and general boundary conditions are derived for the cylinder. Norton's model is incorporated into rate forms of the above-mentioned equations to obtain time-dependent stress and strain results using an iterative method. The redistribution, displacements, strains and stresses over time have been obtained by the semi-analytical iteration method. Moreover, the effectiveness of the proposed method in addressing axisymmetric cylindrical shells under various boundary conditions and thermo-mechanical loading is demonstrated. A parametric study on the creep behavior has also been carried out which reveals critical insights. Notably, the study demonstrates that effective stress and radial displacement during creep can be effectively managed by optimizing the external cooling profile or the internal heating profile. Furthermore, the investigation reveals that the presence of a heat source markedly influences the effective stress and displacement within structure, highlighting the interplay between thermal and mechanical factors in determining the structural integrity. To validate the findings of this study, the finite element method was employed, with the results indicating good agreement between the two approaches.

Hybrid nanoparticles, which are nanoparticles composed of multiple materials or phases, find applications in various fields due to their unique properties resulting from the combination of different materials. In such fluids, viscosity changes significantly in response to alterations in temperature or pressure. For example, these fluids become less viscous as they are heated and more viscous as they are cooled. Similarly, in certain situations, the application of a temperature variation can cause a change in viscosity. This property is commonly observed in materials like polymers and some oils. The article aims to investigate the heat transfer and flow behavior of fluid from an elastic sheet of hybrid nanoparticles, considering the temperature-dependent variable viscosity and thermal conductivity. The obtained equations for the mathematical model are partial differential equations converted to ODEs by applying a suitable similarity transformation. The findings show that the magnetic field opposes fluid motion. Our main findings are that adding nanoparticles to the base fluid significantly increased its heat conductivity. This improvement has great potential for uses requiring effective heat transmission, especially in engineering systems where heat dissipation plays a crucial role. The study also reveals the complex relationships that influence thermal conductivity, including slip boundary effects, viscosity fluctuations, magnetohydrodynamic effects, and porous media dynamics. Understanding these interactions is critical for optimizing heat transport processes in porous media applications. Comprehending these interplays is essential for refining heat transport mechanisms in applications involving porous media. The graphical representations are used to explain the physical behavior of various model parameters. Previous outcomes are also contrasted with the current ones. The findings show that the magnetic field opposes fluid motion.We range the subsequent list of values for parameters in every graph unless indicated accordingly.ϵ=0.1,Pr=2,M=0.5,R=0.2,K=5,fw=0.1,s=0.1 ,λ=1,φ1=0.02,φ2=0.04.

The current study is inspired to investigate the influences of essential flow dynamics including magnetic field, variable dynamic viscosity, Joule heating, viscous dissipation, porous medium dissipation, heat source, thermal radiation, and convective heating on the mixed convection flow of Eyring-Powell Cu − water nanofluid trough an inclined microchannel in the presence of Darcy-Forchheimer porous medium. The governing mathematical model equations are formulated, converted into dimensionless and thereafter solved numerically in the MATLAB software via Bvp4c-package. The influences of the embedded dimensionless parameters on heat transfer behaviours and entropy generations are displayed trough graphs as well as their physical interpretations are discussed in detail. Consequently, it is revealed that the performance of microchannel thermal system is improved by factors such as injection/suction of fluids, Eyring-Powell fluid, magnetic field, non-Darcy porous medium, Cu − nanoparticles, thermal radiation and convective heating. The drag coefficient and Nusselt number augment with viscous dissipation, variable dynamic viscosity, Darcy porous medium, angle of inclination, Prandtl number and heat source. Moreover, the Nusselt number at around the left and right walls vicinity shows an opposite behaviour with escalating values of the Biot number and thus convective transfer of heat around the microchannel walls is remarkably important. Furthermore, the minimization of net entropy generation rate is achieved with Eyring-Powell fluid, magnetic field, Cu − nanoparticles, thermal radiation and convective heating but it escalates with variable dynamic viscosity, viscous dissipation, angle of inclination, heat source and Prandtl number. Indeed, the irreversibility due to the robust influence of porous medium shows dual behaviours on the net entropy generation rate. Finally, the numerical results are also validated by comparing with the results of already existing literatures and hence, a sounding agreement is attained.

The main goal of present research is to illustrate the frequency and amplitude behavior of heat and mass transfer of Darcy Forchheimer nanofluid flow with Arrhenius activation energy and thermal radiation effects. The impact of heat generation and chemical reaction on Darcy Forchheimer nanofluid along vertical porous cone is investigated to improve heating durability of thermodynamic systems in this research. The governing mathematical model is moderated in suitable format to construct physical coefficients. The oscillating stokes and primitive coefficients are used to differentiate the model into oscillating and steady forms. The Gaussian elimination and implicit finite difference techniques are used to address the numerical findings. To construct pertinent algorithm in FORTRAN system, the primitive-type variables are used on steady and oscillating models with first law of thermodynamics, nanoparticles and heat generation. The results under defined conditions are reported in numerical and graphical sequence through Tec-plot 360. It is found that the amplitude of surface temperature increases as heat generation increases because heat generation improves the excessive thermal transport. It is depicted that the Darcy-Forchheimer porous material decreases the fluid temperature. It is found that amplitude of mass transfer increases as activation energy and chemical reaction coefficient increases. The oscillating frequency of heat and mass transfer increases as Prandtl number increases. The current mechanism of mass and heat transfer of nanofluid has several uses in mineralogy, cutting tools, lubricating oils, machining operations, heat exchangers, coating sheets, petroleum drilling and cooling of metallic cones.

The thermal case study is conducted by using artificial intelligence to examine the heat transfer traits in Williamson fluid flow with heat source and thermal slip effects. The thermal flow field interacts with the externally applied magnetic field and velocity slip is additionally considered at the surface. The flow is formulated in terms of energy and momentum equations. All inputs (Prandtl number, magnetic field, thermal slip, and Weissenberg number) are represented in a 4 × 72 matrix and the 72 samples of Nusselt number are represented by a 1 × 72 matrix. The samples are randomly divided into three stages: 70%(50) for training, and 15%(11) each for validation and testing. The number of neurons is set to ten. To train the neural networking model, the Levenberg-Marquardt algorithm is employed. The best validation performance is noticed 5.9676e-08. This indicates that the neural network was successfully trained to predict NN at a magnetized surface. For heat generation and thermal slip parameters, the magnitude of Williamson fluid temperature is higher for the non-magnetic flow field. Further, the Nusselt number admits a declining trend for temperature slip, magnetic parameters, and Weissenberg number while it shows inciting values for the Prandtl number.

By following the statistics, over the last few years, the use of Artificial Intelligence conjectured with mathematical models has increased abundantly for physical problems having thermal engineering standpoints. Owning to such importance, we offer Levenberg-Marquadt-based neural networking modeling of non-Newtonian fluid flow at a flat heat-generating surface with thermal and velocity slip effects. A tangent hyperbolic fluid (THF) is considered with the transfer of heat and mass. Heat absorption and generation aspects are carried out by using an energy equation. The equations are reduced by Lie symmetry analysis and solved by shooting. The neural networking model is constructed by using 91 sample values of inputs namely power law index, Weissenberg number, heat generation parameter, and Prandtl number. 63 (70%) for training, while validation, and testing holds 14 (15%), and 14 (15%) respectively. To train the model, the Levenberg-Marquadt backpropagation technique is utilized. Regression analysis enables a satisfactory correlation between the targeted and output values of the non-magnetic Nusselt number on a flat surface for training, validation, and testing. Following the ANN results, the non-magnetic Nusselt number is found to be an increasing function of the Prandtl number, but the opposite is true for the Weissenberg number, and heat production parameter.