This study introduces a novel grooved cone turbulator (GCT) designed to enhance the thermal efficiency of a heated tube. The performance of the GCT-equipped tube was compared to that of a simple cone turbulator (SCT) and a plain tube. To investigate the impact of the GCT's geometric characteristics on hydrothermal parameters, tests were conducted on varying groove diameters (2.5-10 mm), twist angles (0-270 degrees), and pitch lengths (40-70 mm). The results demonstrate that heat transfer is directly correlated with both groove diameter and twist angle, while it is inversely correlated with pitch length. Notably, the use of the GCT increased the Nusselt number and friction factor by as much as 762 % compared to the plain tube and by 221 % compared to the SCT-equipped tube. Among the three configurations tested-plain tube, SCT-equipped tube, and GCT-equipped tube-the GCT achieved the highest thermal enhancement factor (TEF) of 3.42. This optimal TEF of 3.42 was attained with a GCT featuring a twist angle of 90 degrees, a groove diameter of 10 mm, and a pitch length of 5 cm.

This study unveils a specialised swirl flow generator called the twisted hyperbolic turbulator for implementation in heat exchangers. The design of this geometry aims to induce bidirectional swirling flow. The water fluid flows through a heated tube at Reynolds numbers ranging from 2316 to 5096. This study examined the thermal-frictional effects of the new turbulator at various twisting angles ranging from 60 to 360 degrees. The results indicated that as the twist angle rises, heat transfer also increases because of the fluid's intensified swirling and radial motion. Under ideal circumstances, a twist angle of 360 degrees results in a notable increase in heat transfer by 256 % and a pressure drop by 625 %, accompanied by a TEF of 1.84. Longitudinal perforations were added to the selected turbulator at varying dimensionless distances (R = h/r) from the center, ranging from 9 to 3.6, with dimensionless hole diameters (P = h/d) ranging from 9 to 4.5. The results indicated that as the hole distance from the center of the tube increased, the TEF decreased while increasing the diameter of the perforations led to an improvement in TEF. The optimal configuration was found to be at P = 4.5, located at R = 6, resulting in a TEF of 2.02.

This study investigated the impact of innovative clockwise and counter-clockwise twisted triangle-shaped turbulators on thermal-fractional parameters within a constant surface temperature pipe. One of the key features of this turbulator is its unique geometry, which combines the characteristics of twisted tape and louvered strip turbulators. This design allows for the simultaneous generation of radial and swirling flows within the pipe. The effects of various parameters such as twist angles between 60 and 270 degrees, pitch distances from 0 to 10 mm, and different twisting direction sequences were studied. The findings indicate that increasing the twist angle up to 270 degrees simultaneously enhances the Nusselt number and friction factor. However, while the thermal enhancement factor (TEF) increases with a twist angle up to 120 degrees, it begins to decline at angles greater than 120 degrees. Additionally, the results show that increasing the pitch distance up to 5 mm yields improvements in both heat transfer and TEF; however, beyond this distance, both parameters start to decrease. Moreover, the use of this turbulator can increase heat transfer by as much as 4.45 times compared to a smooth pipe. The maximum TEF achieved is 2.66, which occurs with a configuration of three clockwise and three counterclockwise triangle-shaped turbulators at a twist angle of 120 degrees and a pitch distance of 5 mm.

The present work examines the Soret and Dufour significance on 3D flow of THNF (trihybrid nanofluid) over sheet with porous medium, heat radiation and Stephan blowing impacts using two different thermal conductivity models known as HCM (Hamilton-Crosser model) and YOM (Yamada-Ota model). A trihybrid nanofluid consisting of Cu, TiO2, Fe3O4 and propylene glycol (C3H8O2) as the base liquid is utilized. Performance-wise, this suggested model contrasts the two well-known thermal conductivity THNF models, the YOM (Yamada-Ota model) and the HCM (Hamilton-Crosser model). An advanced model for 3D analysis for THNF (trihybrid nanofluid) through Stefan blowing is existing in the Current investigation. This sophisticated study is essential to improving heat transfer efficiency in industrial processes involving intricate fluid flows under magnetic fields, such as nuclear reactor cooling systems, electronic device cooling systems, and aeronautical engineering. By accurately forecasting the behavior of nanofluids, the model aids in the optimization of thermal management in these systems, enhancing system dependability and energy efficiency. The mathematical results of governing comparisons remain acquired through shelling method (Bvp4c). The YOM and MCM models are used to describe how certain physical characteristics (concentration, velocity, and thermal) affect the usual profiles. The velocity profile and rate of heat transmission rise as the Stephan blowing parameter is increased, but the thermal distribution decreases. The Yamada-Ota model outperforms the Hamilton-Crosser thermal conductivity model of THNF in terms of heat transmission competence. The heat transfer rate is increased by 21.87 % for the ternary hybrid nanofluid, 16.56 % for the hybrid nanofluid, and 11.25 % for the mono nanofluid when the nanoparticles volume fraction is increased from 0.01 to 0.04.

In recent years, the rise of machine learning (ML) has prompted researchers to expand the datasets required for optimizing and designing thermal systems. Also, the development and widespread use of electric vehicles (EVs) have surged significantly. However, one of the major challenges associated with EVs is the efficient cooling of Lithium-ion batteries (LIBs). Therefore, the exploration of innovative cooling methods can contribute greatly to the rapidly growing electric vehicle industry. This study focused on investigating the impact of embedding a nickel porous medium around a single 38,120 LiFeO4 cell. To conduct the study, the LIB, along with the nickel porous medium, was placed inside a duct that received a flow of water and Nano-encapsulated phase change materials (NEPCMs). The results obtained from the study indicate that embedding nickel porous media around the LIB led to a significant decrease in the maximum temperature of LIB, more than 40 C, and a remarkable increase in pressure drop more than 100 times. Additionally, it was observed that the decrease in porosity from 1 to 0.97 had a more pronounced effect on pressure drop and the maximum temperature of the LIB's surface, compared to the decrease from 0.97 to 0.95.

A four-level atomic medium driven by probe and control fields is used to control and modify linear and nonlinear absorption and gain. The normal and anomalous dispersions as well as group index are also controlled by the strength and parameters of driving fields. The angular momentum l of the redefined Rabi frequencies of the control fields intensify the number of absorption and gain peaks according to 2l^2 condition. Normal dispersion is observed in the region of gain while anomalous dispersion is noted in the region of absorption. The negative group index is studied in the anomalous dispersive region and the positive group index is associated with the normal dispersion region. The normal/anomalous dispersive region and positive/negative group index region also increased by the angular momentum l of the control fields according to 2l^2 formula. A positive group index of 1000 is calculated, which reduces the group velocity to 3× 10^5 m/s . An approximate negative group index of -1000 is calculated, demonstrating superluminality of the group velocity at -1/3× 10^5 m/s . The modified results of the current study are useful for speeding up computer chips and time cloak technology.

The role of any fuel cell is direct electricity -generation using electrochemical reaction. However, wasted heat is an unavoidable side -product of any fuel cell. Thermoelectric is another electricity generator producing electricity directly from a source of heat. Hence, this is a potential opportunity to recover the waste heat of the fuel cell by thermoelectric generator meaning higher overall performance of the system. This research proposes and optimizes a novel hybrid fuel cell and two -stage thermoelectric generator to catch the mentioned goal of the research. In this hybrid -system, the serpentine channels of the fuel -cell are directly in contact with ceramic layer of a two -stage thermoelectric generator. The proposed configuration is investigated using a validated 3D -finite element -method. A comprehensive parametric analysis is provided to optimize the system. The results reveal a great performance for the suggested two -stage TEG configuration when the high -temperature skutterudites and low -temperature bismuth tellurides are employed in the high -temperature and the low -temperature stage respectively. The overall -output -power enhances 2.73 -fold in the optimized configuration. Increasing the overall thickness enhances output power, with a notable 233 % increase, when h t goes from 1 to 4. A remarkable 209 % growth is shown when the number of thermocouples in the low temperature stage increases from 36 to 144.

The environmental advantages of hydrogen as a clean energy carrier are more prominent when it is produced utilizing renewable resources. In this regard, a novel geothermal energy driven electricity generation system integrated to hydrogen production plant is developed and investigated in this research. In the developed plant, a PEM electrolyzer is employed for hydrogen generation such that its required electricity is provided by an improved double -flash geothermal cycle. A self -superheater is applied for superheating the vapor at the steam turbine inlet using the geothermal resource to enhance the hydrogen production capacity. To evaluate feasibility of such superheating process and to examine its effects on hydrogen production, thermodynamic models are developed based on first and second laws. Also, environmental considerations are considered in evaluation of the proposed plant performance based on exergo-environmental indices. The influences of first and second flashing pressure, geothermal source temperature and current density of water electrolyzer on energy and exergy efficiency, hydrogen production rate, and environmental damage index are investigated. After carrying out a parametric study, the optimum operation point of the plant is determined via a two -objective optimization based on the hydrogen rate and environmental damage index ( EDI ). It is found that, under optimum operation, the system can produce 25.48 kg/h of hydrogen, while its environmental damage index is calculated to be as 0.00645.

Here, vibration of double walled carbon nanotubes is evaluated using Euler-Bernoulli beam model. These tubes are placed on Winkler elastic foundation. A simple Galerkin's approach is presented to solve the tube governing equations and for extracting of vibration eigen-frequencies of double walled carbon nanotubes. The procedure is easy for computer programming with various combinations of boundary conditions. The frequency influence is observed with different parameters. Effects of Winkler foundation versus frequencies with varying lengths is examined for a number of boundary conditions. It is noticed that the frequencies are lower for higher length on increasing the Winkler foundation. The frequencies of clamped-clamped are higher than that of clamped simply supported end condition. The obtained results are compared with some experimental ones.

Effects of MHD slip flow of second grade fluid with heat transfer are studied in the presence of heat source along permeable stretching surface. The governing boundary layer equations are complex and partial in nature. Using Lie group theory the suitable similarity transformation is derived. The system of PDEs is transformed to system of ODEs by applying these similarity transformations. The combined effect of Hartman number and porosity on velocity profile and the influence of slip parameter on fluid velocity is observed. It is found that enhancing the second grade parameter, boundary layer thickens and ultimately speedup the fluid. Also, the effect of suction/injection parameter on velocity profile is checked. An excellent agreement is noticed that assures the correctness of results. Effects of various physical parameters on the velocity and temperature profile are elaborated with graphs.

In the modern era, Artificial Intelligence (AI) has emerged as a powerful tool that can rapidly generate highly accurate data, offering tremendous potential for optimizing system performance. This study focuses on harnessing the capabilities of an artificial neural network (ANN) to determine optimal parameter values for heat transfer in a mixed convection mechanism. The first step of this research involved conducting CFD simulations to investigate the impact of varying Grashof numbers (102,103,and104), Reynolds numbers (1,10,and100), and MWCNT volume fractions (0, 0.01, 0.02, and 0.03) on the Nusselt number within an elliptical enclosure containing a centrally located rotational cylinder. A total of 48 simulations were performed, generating a comprehensive dataset for training the ANN-Multilayer Perceptron (MLP). In the second step, the trained ANN was utilized to generate an additional 700 data points with remarkable accuracy. This enabled efficient exploration of the parameter space, providing valuable insights into the system behavior and facilitating optimization efforts. The findings of this study revealed a 0.03 vol fraction of MWCNT into the water in Grashof numbers of 102,103,and104, the average Nusselt number increased by approximately 46%, 31%, and 12%, respectively. The ANN-based approach successfully identified optimal values for the variables that maximize the Nusselt number.

This paper examines the wave velocity of protein microtubules using a elasticity model that incorporates body forces, based on the structure of these hollow cylinder-like structures., the governing equations are analytically solved to determine how the body forces effect the wave velocity. To analyze the microtubule waves velocity, use microtubules with simply supported ends. The electric field of a dipole vibrating at the same frequency as microtubule vibrations approximates the electric field generated by the rhythmic motion of every charge. The numerical findings for the three modes of frequencies in the longitudinal, radial, and torsional directions for the current conditions are compared with the results of previous calculations.

Hybrid nanofluids are employed to enhance the antibacterial effect produced by solar radiation. Antimicrobial properties are present in metal nanoparticles (such as silver, copper, or zinc) or metal oxides (such as titanium dioxide or zinc oxide) when exposed to solar radiation. Nanomaterials that have antimicrobial properties are selected from the available literature. A solar sheet with an inclined plane has been chosen and filled with tri-hybrid nanofluids (THNFs). Hybrid nanofluids including (CuO), Copper oxide, TiO2 (Titanium oxide), and SiO2 (Silicon dioxide), are selected from metal and metal oxide classes including water as a base fluid. The antimicrobial action caused by solar radiation is enhanced by the slip boundaries and variable porous space. The influence of flow and thermal fields on isotherms, velocities, flow lines, and Nusselt numbers are considered. The transformed system of differential equations is solved by the Control Volume Finite Element Method (CVFEM) and RK-4 technique. The nanoparticulate volume fraction of CuO, TiO2, and SiO2 is largely responsible for the enhancement in the heat transfer rate (HT), as observed. Improved thermal performance is achieved through the flow of THNFs, which in turn acts as an antimicrobial agent. Increasing values of (phi=phi 1+phi 2+phi 3,M,Ec,Rd,Q)$(\phi = {\phi }_1 + {\phi }_2 + {\phi }_3,M,Ec,Rd,Q)$ parameters lead to an improvement in the heat transfer rate, which in turn decreases microbial activity.

For the purpose of enhancing the thermal efficiency of double-tube heat exchangers, a new technique has been implemented. By integrating a vibrating turbulator and bubble injection technique, this innovative method produces an added turbulence effect. This research aims to experimentally assess the thermal efficiency of employing two active methods concurrently. Different parameters were analyzed, including water flow rates ranging from 0.5 to 4 kg/min and bubble injection flow rates varying from 2 to 6 l/min, to investigate the effects on heat transfer and pressure drop with and without the magnetic turbulator. The results suggest that by incorporating bubble injection, adopting the magnetic turbulator, and simultaneously utilizing both methods, there is a significant improvement in heat transfer. In optimal scenarios, the heat transfer coefficient is amplified by 150.3% through the injection of bubbles, 328.8% through the implementation of magnetic turbulator, and 586.2% when both techniques are employed in tandem. In comparison to the smooth tube, the friction factor ratios were 6.7, 1.6, and 7.8 times higher in the specified cases. The findings indicated that the concurrent utilization of both techniques can yield an added impact on heat transfer. Ultimately, the integrated approach demonstrated a noteworthy thermal enhancement factor value of 3.49.

The purpose of the article is to design, evaluate, and compare four different pathways implemented in the Corn Stover-driven biorefineries. These pathways are based on biohydrogen production via Photo-fermentation (PFBHP) or dark fermentation (DFBHP), biomethane production (BMP), and bioethanol production (BEP). A comprehensive examination and analysis of the mentioned pathways in terms of the kinetic properties, greenhouse gas emissions, and economic feasibility was developed. The research problem addressed is the lack of a comprehensive, comparative analysis of these pathways under consistent conditions, limiting informed decision- making for large-scale biorefinery implementation. The maximum outputs of the PFBHP, DFBHP, BMP, and BEP pathways were around 68.5 mL per gram DM (dry matter) at 25 g DM per Liter, 48.0 mL per gram DM at 25 g DM per Liter, 0.19 L per gram DM at 4 % TS, and 0.05 g per gram DM at 55 g DM per Liter. Additionally, the BMP pathway achieved the maximum energy output, peaking at around 7.02 kJ/g DM under 4 % TS. Further, the PFBHP pathway emerged as high-economic value method, with the peak economic value being 0.20 US$ per kg DM. The PFBHP and DFBHP methods were environmentally favorable, emitting no greenhouse gases.

Entropy generation and convection heat transfer in a partially porous chamber with different side wall temperatures using CuO -H 2 O have been investigated. The importance of this issue is wide application of the results in solar collectors, thermal extrusion systems, heat exchangers, biomedicine, nuclear waste disposal, etc. The innovation of the present work is related to the investigation of fluid and heat fields and entropy generation by using a matrix with subordination of porosity to the vertical axis and permeability, thermal conductivity, and viscosity with subordination of porosity. To obtain accurate results, the two-phase mixture model was used, and thermal conductivity and viscosity of nanofluid were simulated by experimental models by temperature and volume fraction dependence. Governing equations are solved by the FVM. The main findings indicate that the best and worst optimization factor will occur in the porous matrix epsilon = epsilon(y 2 ) and epsilon = - epsilon(y 2 ), respectively, which is 113 % and 86 % of N H of the homogeneous matrix, respectively. Also increasing the filling of the cavity, highly improves N H , so that the N H will reach from 1.19 to 1.82 with the increase of S from 0.25 to 1.

The interaction of short range zigzag single walled carbon nanotubes CNTs based on modified elasticity model is studied in this paper. The numerical accurate results are presented. Through this model the vibrational frequency of zigzag (5, 0), (12, 0) single-walled CNTs with certain end conditions are estimated. The natural frequencies of single walled carbon nanotubes are obtained by elasticity model. It is considered for various estimation of height-to-diameter ratio of zigzag tube. This simulation is performed to quantify small scale effects. Moreover, the natural frequencies increase by increasing the height-to- diameter ratio. These frequencies are very sensitive with low height-to-diameter ratio. The feasibility and effective use of present model is explained by comparison of outputs of earlier investigations.

Latest advancement in field of fluid dynamics has taken nanofluid under consideration which shows large thermal conductance and enlarges property of heat transformation in fluids. Motivated by this, the key aim of the current investigation scrutinizes the influence of thermal radiation and magnetohydrodynamic on the laminar flow of an incompressible twodimensional Williamson nanofluid over an inclined surface in the presence of motile microorganism. In addition, the impact of heat absorption/generation and Arrhenius activation energy is also examined. A mathematical modeled is developed which stimulate the physical flow problem. By using the compatible similarities, we transfer the governing PDEs into ODEs. The analytic approach based on Homotopy analysis method is introduced to impose the analytic solution by using Mathematica software. The impacts of distinct pertinent variable on velocity profiles are investigated through graphs.

The calculation of the natural frequencies versus Young's modulus of carbon nanotubes with modified continuum shell is the subject of current research. When designing these tubes, it is important to understand their frequencies because excessive vibrations might cause fatigue. These tubes are designed and built to meet specific needs and have been suitably modified to investigate their vibratory response. There are numerous uses for carbon nanotube free vibration analysis in the mechanical sciences. The fundamental frequency with Young's modulus for clamped-free and simply supported end conditions, which is connected to the carbon nanotubes, is calculated theoretically for chiral single carbon nanotubes. When Young's modulus rises, so does the frequency curve pattern. Young's modulus influences the single-walled carbon nanotube's dynamic response by simulating it as a modified continuum shell. The Young's modulus of chiral tube and the value of frequency increased as the chiral tube's index increased. The results are checked against past studies to ensure the problem's validity and are determined to be accurate.

Hybrid nanofluids are capable of being used as a carrier for delivering drugs to targeted areas in the body. For this purpose, the Casson hybrid nanofluids (HNFs) flow is suggested between the gap of two tubes. The study involves analyzing blood-based hybrid nanofluids (HNFs) that consist of silver (Ag) and titanium dioxide (TiO2) nanoparticles for applications of drug delivery. Titanium oxide nanoparticles, or TiO2 NPs, have strong photoactivity, low toxicity, and excellent biocompatibility, making them promising candidates for cancer treatment. The attractiveness of silver nanoparticles (AgNPs) for cancer therapy is due to their unique properties. Graphic representations are provided based on the simulations of non-dimensional velocity, temperature, and skin friction under physical parameter variations, for the applications of drug delivery are investigated and discussed. The control volume finite element method (CVFEM), is used to solve the problem. The new strategy of artificial neural networks (ANN) is also used to solve the transform equations. Nanoparticles increase drug stability and extend shelf life by protecting them from degradation or inactivation.