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This study focused on addressing the heat generation issue in Lithium-Ion battery packs (LIBPs). By simulating three LIBPs arranged in series within a duct, the momentum and energy conservation equations were solved using Computational Fluid Dynamics (CFD) to investigate cooling performance on the LIBPs' temperature. To enhance cooling, copper oxide nanoparticles were added to pure water to improve the thermal conductivity of the working fluid. Various cases were simulated to examine the effects of Reynolds number at inlet and volume fraction of copper oxide nanoparticles on flow parameters (streamlines, vortices, pressure drop) and heat transfer parameters (temperature distribution, maximum and average temperature of each LIBP) within the duct. Also, this study analyzed exergoeconomics by considering exergies and initial investment. The results demonstrate that increasing the volume fraction from 0 to 4 % at Re = 60 reduced the maximum temperature of LIBP 1, 2, and 3 by 2.19 °C, 2.26 °C, and 2.64 °C, respectively, while it had no remarkable impact on the maximum temperature of LIBPs for bigger Reynolds numbers.

Today, every device that a person uses depends on electronic equipment, frequent and long-term use of it causes to heat up and as a result, slow down the speed and performance of that device. In more important and sensitive equipment such as medical equipment, slow speed and reduced performance cause irreparable damage. Therefore, to cool these devices, their internal electronic equipment must be cooled. In studies by others, the simultaneous use of several phase change materials and airflow in the form of layer-by-layer contact was usually less studied. In this study, using CNC machining, a heatsink consisting of 2 spirals was produced. In the first spiral, PCM Paraffin Wax with different volume percentages and in the second spiral, the presence or absence of forced airflow in heat transfer rate 2.9 W to 3.7 W was tested with a step of 0.4 W and the results were that by adding %50 PCM and adding 100 % PCM to the system, its performance increases by 7.19 % and 44.91 %, respectively, which shows using the maximum volume capacity of PCM increases efficiency. Also, by adding forced airflow to the system, its performance has increased by 7.71 %. It can be said that if the forced airflow in the system is used layer by layer, it prevents the heat from concentrating in certain parts of the heatsink and the circuit, which results in the same heating of the whole system and the heat is evenly distributed throughout the heatsink.

In the late 1980s, electrically assisted press bonding gained attention in the semiconductor industry due to its ability to improve bond quality and reliability. This bonding method has several advantages, including improved bond strength, reduced bonding time, and the ability to bond materials that are traditionally challenging to bond. This connection method is commonly used in applications where high band strength, reliability, and electrical conductivity are critical, such as microelectronics manufacturing, semiconductor devices, and advanced packaging technologies. In this study, AA1100 bars were connected using an electrically assisted press connection process at current levels of 100A, 200A and 300A. Poor bond strength is an important drawback in bonding processes. Therefore, to solve this problem, Sn particles were used as a finishing process and filler metal to increase the bond strength of aluminum sheets during electric press joining. AA1100 bars were produced with different weight percentages (wt%) of Sn particles as interlayer filler at different levels of electric current. The results reveal that increasing the level of electric current and the weight percentage of Sn leads to stronger bond strength. In this study, a scanning electron microscope (SEM) is used to check the quality of the bond. It is worth mentioning that the analysis of the exfoliation surface by SEM is performed on the samples after the peeling test to check the quality of the bond. In addition, the findings reveal that the bond strength improves with Sn content and higher current levels due to the Joule heating effect in the electrical press bonding process.

Atomic investigation of many common phenomena can be included as interesting achievements. Using these achievements makes it possible to design promising structures for various actual applications. The current research describes the mechanical performance of Ag and Cu samples after welding at various initial pressures. For this purpose, the Molecular Dynamics (MD) approach is used via the LAMMPS package. Technically, MD simulations are done in 2 main steps. Firstly, the atomic stability of welded Ag-Cu samples is described at various initial conditions (initial pressure). Then, tension test settings are implemented in equilibrated systems. The MD outputs indicate that the physical stability of the welded samples was altered by changing the initial pressure between 1 and 10 bar. Simulation results predict that the mechanical resistance of atomic samples decreases by enlarging the initial pressure. Numerically, the ultimate strength of the Ag-Cu matrixes decreases from 1.424 MPa to 1.241 MPa by increasing the initial pressure from 1 bar to 10 bar, respectively. This mechanical performance arises from atomic disorder created inside samples. So, it is expected that initial condition changes affect the atomic evolution of welded metallic samples, and this phenomenon should be considered in the design of mechanical structures in industrial cases.

Phase change materials (PCMs) are materials whose most important property is latent heat capacity, which is an effective and important part of energy storage. These materials can provide or improve thermal comfort conditions through a phase change. A computer mouse is one of the pieces of equipment that are dependent on temperature and causes discomfort to the user if the temperature increases. By placing the hand on the mouse and doing the activity, based on the different metabolism of each person's body, it takes some time until the interface between the hand and the mouse gets hot and causes the user to be annoyed. Based on this, an experimental method was used to investigate the effect of using a PCM on the mouse. In this article, two PCMs (Paraffin Wax and Capric Acid) were used inside four capsule models (A: overall capsule, B: capsule parallel to the X-axis, C: capsule parallel to the Y-axis, D: checkered capsule), and the result was that with the addition of the capsule containing Paraffin Wax, the time to reach the maximum temperature was 7.14% compared to the normal state and with the addition of the capsule containing Capric Acid, the time to reach the maximum temperature will increase by 76.4% compared to the normal state. Regarding the comparison of the arrangement of capsules, the best case is to use a general capsule. But because using this type of capsule makes it difficult for the user, therefore, the best layout is the checkerboard type and increases the mouse’s performance by 76%.

A pillow plate heat exchanger (PPHE) is one of the types of heat exchangers that haven't received the attention they deserve despite their high efficiency and operational capability. A unique feature of PPHEs is their pillow-shaped structure, which is achieved through hydroforming. In light of this, scholars have been interested in analyzing and optimizing the thermo-hydraulic properties of PPHEs. In this study, the interior of the PPHE was occupied with a permeable substance with a high porosity percentage (0.9034 ≤ ɛ ≤ 0.9586 and 0.00015 ≤ dp ≤ 0.00065) and saturated with Ag-water (0 ≤ϕ ≤ 0.06) nanofluid, which has a profound influence on the heat transfer rate of PPHEs. In order to analyze the determinants affecting the heat transfer rate of PPHEs under these conditions, the governing equations were solved using the finite volume method and also the Brinkman-Forchheimer-extended Darcy equation. According to the results, heat transfer is enhanced in PPHE when using a permeable medium with high porosity and a small pore size. That is, PPHEs transfer heat more efficiently when they are placed in a denser porous medium because heat conduction is boosted. Moreover, due to the increased thermal conductivity of the nanoparticles, the application of nanoparticles to the base fluid also enhanced heat transfer and Nusselt number. However, decreases in friction factor and entropy generation were observed with increasing porosity, pore size, and Darcy number, due to reduced flow resistance. A decrease in Richardson number also results in a decrease in friction factor and entropy generation. At the wake region of welding spots, the velocity has reached its lowest values; consequently, this led to a reduction in the heat transfer rate. Nevertheless, within dense porous media, at the lower hydraulic diameter points, the conduction contributes to heat transfer improvement. The porous medium acts as a heat sink and absorbs the heat from the welding spot. This allows the heat to be dissipated away from the welding spot, which reduces the velocity and heat transfer rate. The nanofluid, on the other hand, helps to increase the thermal conductivity of the medium, resulting in more heat being transferred to the surrounding material. Consequently, the results demonstrated that PPHEs' thermal and thermodynamic performance could be significantly improved by using a porous medium saturated with nanofluid.

In recent years, the lattice Boltzmann method has become a powerful method for computational modeling of various complex fluid flow concerns, including the simulation of the melting process in phase change materials. In the present paper, the natural convection of phase change materials in a cavity is simulated, and the effect of adiabatic obstacle and fin is investigated by the lattice Boltzmann method. The obtained results are presented in different Rayleigh numbers (Ra = 103-105), and cavity angles (θ=-90to90) in three scenarios (without adiabatic fin and obstacle, with an adiabatic obstacle, and with adiabatic fin). The investigation across various cavity angles, with adiabatic obstacles and fins, demonstrates a consistent trend of effective melting process delay by up to 50%, underscoring the significant impact of these adiabatic features on PCM behavior. Adiabatic obstacles induce localized melting delays due to unmelted zones around them. Streamlines highlight vortices formed by obstacles, and elevated Nusselt numbers correlate with accelerated melting facilitated by adiabatic fins. Modifying the adiabatic fin height from Yf = 0.1 to Yf = 0.7 leads to a doubling of melting time at around 80% PCM melting. Conversely, decreasing fin height from 0.5 to 0.7 extends the complete melting time by approximately 10%, showcasing the influential role of fin height in shaping PCM melting behaviour.

Hybrid composites (HC) refer to a type of material that combines aluminum (Al), titanium carbide (TiC), and graphite (Gr) at the nano level. These HC have shown promise in applications requiring high strength, wear resistance (WR), and tribological performance, such as automotive, aerospace, and industrial sectors. In this study, these HC are made using a combination of Powder metallurgy (PM) and accumulative press bonding (APB) processes have been developed. This is the first time that the wear resistance of a hybrid metal matrix composite fabricated with Gr as a solid lubricant has been done and thid is the novelty of this study. In fact, the presence of TiC nanoparticles (NP) provides improved mechanical properties, such as hardness (Hr), strength, and WR for HC. On the other hand, Gr acts as a solid nano-lubricant (NLU) in HC, reducing friction and WR during sliding contact. The presence of Gr-NP also helps to form a durable Gr-nanolayer on tribo surfaces and further improves the WR of HC. This study used a scanning electron microscope (SEM). The results demonstrated that incorporating TiC- NP reduced the WR rate and promoted NL development at extended sliding distances, creating a durable TiC/Gr HC on the TS. Finally, the improved WR of Al/TiC/Gr-HC can be attributed to the stability of the Gr-NL on the TS.

The main uses of bullets are as projectiles in firearms for military, law enforcement, and civilian purposes. However, bullets have significant industrial applications beyond their role in weaponry, such as precision drilling, cutting, and shaping of hard materials. Steel bullets have a very resistant structure and will not be damaged if exposed to corrosion. Other applications that are resistant to strike and projectiles, such as the automotive and aerospace industries, are based on fibers or fabrics with high toughness and tensile strength, such as Kevlar and p -aramid fibers, which are impregnated with some thermoplastic or thermoset polymers. Therefore, in the upcoming research, the impact of external force (EF) with various values (0.1, 0.2, 0.3, 0.4, and 0.5 V/Å) on the strength of Kevlar nanofibers reinforced with silicon dioxide (SiO2) nanoparticles and ethylene glycol (EG) has been investigated using LAMMPS software. EG and SiO2 nanoparticles with 10 and 2 vol% were added to Kevlar fabrics, creating a shear thickening fluid (STF) nanocomposite. The energy parameters of the interaction between the particles, collision velocity, and the center of mass have been calculated. The findings of the research indicate an increase in the interaction energy from 111271.85 to 154351.15 kcal/mol, an increase in the collision velocity from 0.7046 to 1.5812 Å/fs and an increase in the center of mass from 0.62671 to 1.1670 Å due to the EF applied from 0.2 to 0.4 (kcal/mol)/Å. These results show EF should be optimized in actual cases for the collision process to occur effectively.

Nano-pump is a breakthrough that allows a tiny pump to transfer mass inside the atomic channels. These nanostructures can be used in various applications, such as drug delivery systems in clinical cases. Carbon nanotube (CNT) performance as a nano-pump sample was introduced here. For this purpose, Molecular Dynamics (MD) approach, and external heat flux/electric field effect on nano-pump performance were reported. Hence, various physical parameters, such as nano-pumping time, potential/kinetic energy, stress and entropy were reported to describe the nano-pumping performance of CNT samples. Technically, nano-pumping performance was detected by fullerene (C20) molecule displacement inside the NT. The MD outputs indicated by the heat flux implemented inside CNT, nano-pumping process effectively occur. The results show that by increasing the heat flux amplitude ratio from 0.1 to 0.5 W/m2, the displacement time of C20 molecule decreased from 7.49 to 6.96 ps. By amplitude enlarging, the kinetic energy of defined sample converged to 5.70014 eV. This procedure caused more atomic collisions inside the NT, and the nano-pumping process occurred in a smaller time. Furthermore, the electric field caused the nano-pumping process to be delayed in modeled systems. Numerically, by increasing the electric field, the nano-pumping process occurred after 7.85 ps. Increasing the electric field decreased the mechanical wave produced via Cu tip oscillation. This evolution caused the atomic force, and stress on the target particle converged to a lesser value, and the lattice stress value of modeled sample reached 2.12662 × 106 bar.

Recently, oscillating heat pipes (OHPs) filled with nanofluid (NF) as the operating fluid has drawn researchers’ attention because of their improved thermal conductivity, and heat/mass transfer (HT/MT) characteristics. An OHP is an HT device based on a two-phase fluid flow that transfers heat between heat sources and heat sinks which is applicable in industries in terms of its highly effective thermal conductivity. According to previous research, in previous experimental and computational studies, the effect of adding metal oxide NPs into the operating fluid of an OHP was not studied. Therefore, adding Fe3O4 NPs to the operating fluid of the water flowing into an OHP with nano dimensions will be the research work ahead that can increase the efficiency of designed structures. The maximum density, velocity, temperature, and heat flux after 20 ns are examined to determine the effects of NP size and an external magnetic field (EMF). The numerical findings show that heat flux increased from 1561 to 1602 W/m2 when the NPs' size grew from 5 to 10. Therefore, the HT/MT of Fe3O4-H2O simulated NF showed enhanced thermal behavior as NP's radius increases. Furthermore, the results show that the presence of an EMF enhanced the thermal behavior of NF in the OHP. The heat flux increased from 1563 to 1586 W/m2 when the magnetic field magnitude increased from 1 to 5 T.

Particulate matter (PM) with a diameter of less than 10 µm is among the pollutants in cities that can be inhaled by humans. They are 100 µm in size and are neutralized by the lungs' cleaning system. Particles with a size of 2.5 µm cause cardiac and pulmonary discomfort by settling in the respiratory system. In this research, the absorption of PM by the respiratory system simulated with CFD has been investigated. Also, the effect of using a mask with a porosity of 0.07 and 0.2 on the absorption of PM has been investigated. The results show that the percentage of particle absorption for laminar flow and flow rates of 20, 25, and 30 lit/min is equal to 96.87 %, 97.19 %, and 97.64 %. With the increase of fluorite, the percentage of absorption of particles also increases. The percentage of particle absorption for turbulent flow and flow rates of 40, 60, and 100 lit/min is equal to 98.67 %, 98.65 %, and 99.59 %. With the increase of fluorite, the percentage of absorption of particles also increases. The absorption of particles for 1, 2.5, and 10 µm is close to each other for laminar respiratory flows, while it does not show this in a turbulent flow. The respiratory filter with a porosity of 0.07 is ideal and can filter particles up to 99 %. According to the results obtained in this project, in the porosity of 0.07, the filtration of 1-µm particles is the best compared to the rest of the investigated porosity.

The stability of the SARS virus can be affected by various environmental factors, including temperature, humidity, and pressure. In the present research, the effect of initial pressure on the stability of the SARS virus in the presence of water/Ag nanofluid (NF) is investigated using molecular dynamics (MD) simulation. The results revealed that initial pressure effectively changes the atomic evolution of the virus-NF system. Numerically, the diffusion coefficient of modeled samples changes from 32.33 nm2/ns to 9.489 nm2/ns by initial pressure varies from 1 bar to 10 bar. This structural evolution caused interatomic distance and force between virus particle changes. Finally, interaction energy is changed by initial pressure variation, and this parameter varies between −0.44695 kcal/mol to −24.65127 kcal/mol in defined initial conditions. From MD outputs, it was concluded physical stability of the SARS virus in the presence of water/silver NF can be manipulated by initial pressure. So, the SARS virus destruction process with water/silver NF affected from the initial pressure ratio, appropriately. Future directions for this research project may involve exploring the influence of additional environmental factors and utilizing the gained knowledge to develop antiviral materials. This study establishes a foundation for further investigations into the interaction between environmental factors, NFs, and viral infections, with the potential to contribute to the development of effective strategies for combating viral infections and designing innovative antiviral solutions.

Much research has been done on the behavior of pneumatic tires and this has resulted in many different tire models and measurement data. However, not much data is available in the specific area of the effect of the capply layer on the stability of the vehicle. In this research, the effect of the length of the capply layer on the longitudinal and lateral stiffness was investigated. Also, two models of the suspension system were simulated and their important parameters were calculated, including the displacement of the sprung mass, the displacement of the unsprung mass, and the tilt angle. In the next step of the simulation, using the CARSIM software, the effect of the length of the capply layer on the stability of the car was investigated. The results show that the number of lateral stiffness increases with the increase of the capply layer. By increasing the length of the capply layer of the tire, the layers that have a great effect on the longitudinal stiffness of the tire are reduced. By applying a step input with a range of 10 mm to the system, the maximum initial peak is observed in the length of the 6 mm capplay layer and the minimum peak is observed in the 16 mm capplay layer. The maximum tilting angle in this system is equal to 0.006 rad, which is considered a small value for the system. With the increase in the length of the capply layer, the ride quality of the car decreases. An increase of one millimeter in the capply layer can increase the stability of the car by 18 %.

Reducing fuel consumption and increasing efficiency is one of the solutions that humanity has adopted to reduce costs caused by fuel consumption in all industries, including the transportation industry. An effective solution to improve practical fuel consumption is to reduce weight. In principle, press bonding (PB), which is done using a press and is a solid-state welding process, can create a bond between parts with different materials and produce materials with lighter weight and more strength. But it should also be noted that the plasticity of some materials is very low, and these materials are incapable of machinability. Electrical assistance is a potential solution that can solve this problem by increasing the flow tension and reducing the forming force. In this study, aluminum alloy 1060 bars were electrically press bonded at electricity current levels 0 Å up to 300 Å. The effect of pressing parameters on the bonding strength, such as amount of electricity current level and plastic strain, was investigated using a peeling test. Results show that more adhesive among the layers (bonding strength) was attained by growing current and reducing thickness. Scanning electron microscope (SEM) was investigated the peeling surface of samples versus the different thickness reduction ratios and electric currents. The Joule heating effect in the electrically-assisted in press bonding (EAPB) process decreases the forming strength of bars and increases the bond strength of bonded bars by about three times. Using SEM, the peeling surface of samples and the fracture surface around the interface after the tensile test were studied to investigate the bonding quality.

The mechanical properties of paraffin-reinforced silica aerogel are important to ensure structural integrity in industrial applications, inform material development, and optimize overall performance and durability. Moreover, they contribute to innovative material research and the development of advanced materials with improved strength and multifunctional properties. This study aimed to examine the mechanical performance of paraffin-reinforced silica aerogel by focusing on the ultimate strength, Young's modulus, and stress–strain curve values affected by different ratios of external heat flux (0.1 to 1.0 W/m2) using molecular dynamics simulation. The results show that by increasing the external heat flux from 0.1 to 0.3 W/m2, the ultimate strength, Young's modulus of the simulated sample increased from 414.91 and 1223.87 MPa to 421.39 and 1288.66 MPa, respectively. Furthermore, by further increasing the heat flux to 1.0 W/m2, the mentioned parameters declined to 409.61 and 1276.88 MPa, respectively. Additionally, the study showed that higher heat flux levels caused an increase in the amplitude of atomic fluctuations, leading to a decrease in the physical stability of sample. The findings indicate the significant effect of external heat flux on the mechanical properties of aerogel, and highlight its potential to either impair or improve the mechanical strength of structure with implications for various industries.

Amidst escalating fuel expenses and growing concerns over greenhouse gas pollution, the adoption of renewable alternative energy sources has become increasingly imperative. In response, scientists are fervently dedicated to identifying energy-saving solutions that are readily adaptable. Notably, silica aerogels have demonstrated remarkable efficacy in temperature management under both hot and cold conditions, while phase change materials are renowned for their capacity to store thermal energy. The study examines the effect of initial pressure on the thermal performance of silica aerogel/PCM/CuO nanostructure in a cylindrical duct. This was investigated using MD simulations and the LAMMPS software. The study will investigate several elements, such as density, velocity, temperature patterns, heat flux, thermal conductivity, and charge time or discharge time of the simulated structure. According to the results, with an increase in the initial pressure, the maximum density increases from 0.0838 atom/Å3 to 0.0852 atom/Å3, and the maximum velocity decreases from 0.0091 Å/fs to 0.0081 Å/fs. Also, the findings show that, by increasing the initial pressure, the temperature decreases from 931.42 K to 895.63 K, and thermal conductivity and heat flux decrease to 1.56 W/m.K and 56.66 W/m2 with increasing the initial pressure to 5 bar. Finally, the results show that charging time increases to 6.34 ns at 5 bar. The increase in charging time with increasing initial pressure may be attributed to the reduced mobility of particles within the structure as a result of the higher pressure. The findings of this study can help for a better understanding of energy-saving solutions, advanced thermal management systems, and the design of efficient energy storage technologies tailored to specific pressure-related operating conditions.

One of the most crucial concerns is improving industrial equipment's ability to transmit heat at a faster rate, hence minimizing energy loss. Viscosity is one of the key elements determining heat transmission in fluids. Therefore, it is crucial to research the viscosity of nanofluids (NF). In this study, the effect of temperature (T) and the volume fraction of nanoparticles (φ) on the viscosity of the silica-alumina-MWCNT/Water hybrid nanofluid (HNF) is examined. In this study, a nonlinear curve fitting is accurately fitted using MATLAB software and is used to identify the main effect, extracting the residuals and viscosity deviation of these two input variables, i.e., temperature (T = 20 to 60 °C) and volume fraction of nanoparticles (φ = 0.1 to 0.5 %). The findings demonstrate that the viscosity of silica-alumina-MWCNT/ Water hybrid nanofluid increases as the φ increases. In terms of numbers, the μnf rises from 1.55 to 3.26 cP when the φ grows from 0.1 to 0.5 % (at T = 40 °C). On the other hand, the μnf decreases as the temperature was increases. The μnf of silica-alumina-MWCNT/ Water hybrid nanofluid reduces from 3.3 to 1.73 cP when the temperature rises from 20 to 60 °C (at φ = 0.3 %). The findings demonstrate that the μnf exhibits greater variance for lower temperatures and higher φ.

Nanofluids (NFs) are nanoscale colloidal suspensions containing dense nanomaterials. They are two-phase systems with solid in liquid phase. Due to their high thermal conductivity, nanoparticles increase the thermal conductivity (TC) of base fluids, one of the basic heat transfer parameters, when distributed in the base fluids. The present research investigates the thermal behavior, Brownian motion, and thermophoresis of water/graphene NF affected by different numbers of atomic wall layers (4, 5, 6 and 7) by molecular dynamics (MD) simulation. This investigation reports changes in heat flux (HF), TC, average Brownian displacement, and thermophoresis displacement. By raising the number of atomic wall layers from 4 to 7, the average Brownian displacement and thermophoresis displacement increase from 3.06 Å and 23.88 Å to 3.62 and 25.05 Å, respectively. Increasing the number of layers due to the decrease in temperature increases the temperature difference between the hot and cold points along the channel. It increases the Brownian motion and the maximum temperature. Additionally, by raising the atomic layers of the channel wall, the values of HF and TC increase from 39.54 W/m2 and 0.36 W/mK to 41.18 W/m2 and 0.42 W/mK after 10 ns, respectively. The temperature rose from 1415 to 1538 K. These results are useful in different industries, especially for improving the thermal properties of different NFs.

Integrating cooling systems with photovoltaic-thermal (PVT) collectors has the potential to mitigate the exergy consumption in the building sector due to their capability for simultaneous power and thermal energy generation. The simultaneous utilization of nanofluid and geometry modification resulted in a synergetic enhancement in the performance of PVTs and thereby reducing their sizes and costs. In addition, there is still a lack of high accurate predictive model for the estimation of the performance of PVTs at a given Re number and nanofluid concentration ratio to be used in engineering design for the further product commercialization. To this end, the current numerical study investigates the exergy electricity, thermal, and overall exergies of a building-integrated photovoltaic thermal (BIPVT) solar collector with Al2O3/water coolant. The increase in nanoparticle concentration (ω) from 0 % to 1 % increased the useful thermal exergy and overall exergy efficiency (Exu,t/ Υov) by 0.3999 %/0.0497 %, 1.3959 %/0.2598 %, and 0.7489 %/0.1771 % at Re numbers of 500, 1000, and 1500, respectively, while Exu,t/ Υov exhibited a reducing trend at Re = 2000; 0.3928 %/0.1056 % decrease. In addition, the increase in ω from 0 % to 1 % caused the useful electricity and electrical exergy (Exu,e/ Υe) to be diminished by 0.0060 %/0.0025 % at Res 500 and 1000, and to be escalated by 0.0113 %/0.0055 % at Res of 1500 and 2000. Meanwhile, the Re augmentation, from 500 to 2000, improved the Exu,t, Exe, Υe, and Υov by 60 %, 1.26 %, 1.26 %, and 17.50 %, respectively, at different ω s. In addition, two functions were developed and proposed by applying a group method of data handling-type neural network (GMDH-ANN) to forecast the value of Υov based on two input values (Re and ω). The results showed high accuracy of the proposed model with MSE, EMSE, and R2 of 0.0138, 0.1143, and 0.99785, respectively.

Metal matrix composites have various structural and thermal applications in terms of their unique mechanical and thermal properties compared to their counterparts. These nanoparticle (NP)-reinforced composites have received much attention due to their relatively low production costs and excellent mechanical properties. In the present research, modeling and studying the effects of adding reinforcing NP on the hardness of aluminium-based composites is done using the molecular dynamics (MD) simulation. The expressed structures' equilibration, temperature, and potential energy are calculated and reported in the first simulation stage. In this regard, the parameters of Lennard-Jones potential function for the particles in the MD simulation of aluminium and oxygen. Finally, the results show that the hardness of pure nanocomposite (NC) was equal to 100, and by adding NP with a mass ratio of 6%, the hardness of NC increased from 100 to 190 HV. The radial distribution function (RDF) showed that the composition was in the solid phase at a temperature of 300 K, indicating the proper balance of simulated atomic systems. The results show that the maximum value of RDF decreased by increasing the amount of reinforcement. The results show that the yield stress decreased as the volume fraction of reinforcement increased in the crystal structure. Finally, it is expected that the results obtained from MD simulations will be considered in the practical use of aluminium NCs reinforced with alumina nanoparticles in various industrial, engineering and medical uses.

One of today's concerns regarding energy storage units is the low rate of storage and release of thermal energy and, as a result, the efficiency loss in these units. Subsequently, different strategies are utilized to solve this concern, such as using phase change materials (PCMs) and nanostructures. The background is the low storage and release rate of thermal energy in energy storage units, which leads to efficiency loss. This issue concerns many applications, including energy storage in buildings, vehicles, and electronic devices. This study aims to investigate the effect of external heat flux (EHF) on the thermal efficiency of a specific heat sink by employing molecular dynamics (MD) simulation. After ensuring the simulated atomic structures are stable, EHF is applied to see how it affects the thermal behaviour of the combination. The obtained results show that by increasing the EHF applied to the prototype, the thermal behaviour of the structure improves. So, with the increase of EHF from 0.1 W/m2 to 0.5 W/m2, the heat flux and thermal conductivity (TC) increase from 212.27 W/m2 to 317.90 W/mK to 286.71 W/m2 and 340.03 W/mK. The findings significantly affect energy storage unit efficiency and can inform future research and development efforts.

This study focuses on the behavior of the Carbon Nanotube (CNT)-C20 system as a nano-pumping configuration for drug delivery processes. The system was modeled using a molecular dynamics (MD) method, and the effects of external heat flux and silicon doping were investigated. The predicted MD outputs showed high stability throughout the nanopumping process, even when different ratios of external heat flux were applied. The entropy value of the CNT-C20 system decreases from 412.91 to 403.394 eV/K as the heat flux increases to 0.03 W/m2. Also, the kinetic energy of the target atomic sample increased from 3.50 to 5.42 eV as heat flux increased. This kinetic energy enlarging occurred for the translational component of the target molecule’s kinetic energy, and the rotational component didn’t change effectively. Additionally, the results show that increasing atomic doping of silicon particles from 1 to 3 % decreased the displacement time of C20 molecule (7.22 ps for a 3 % doping ratio), indicating that atomic doping may also improve the nano-pumping process. By increasing Si doping to 3 %, the potential energy decreased, and the stability of the defined compound was reduced. This procedure caused the target molecule to not stabilize inside the nanotube sample, and this molecule displaced inside the deliverer system in less time. However, the negative ratio of potential energy showed physical stability of the total system wasn’t disrupted. With further doping increase to 5 %, the defined compound’s potential energy increased and stability enlarged. This process can be delayed nano-pumping procedure. Overall, the outcomes of this simulation provide insights into the optimal method for pumping fluids at the nanoscale and for drug delivery systems. These findings have practical implications for developing more efficient and effective drug delivery technologies that can help improve patient outcomes.

Nowadays, cardiovascular illnesses are among the leading causes of death in the world. Thus, many studies have been performed to diagnose and prevention of these diseases. Studies show that the computational hemodynamic method (CHD) is a very effective method to control and prevent the progression of this type of disease. In this computational paper, the impression of five non-Newtonian viscosity models (nNVMs) on cerebral blood vessels (CBV) is investigated by CHD. In this simulation, blood flow is supposed steady, laminar, incompressible, and non-Newtonian. The parameters of Nusselt number (Nu), dimensionless temperature (θ), pressure drop (Δp), and dimensionless average wall shear stress (DAWSS) are also investigated by considering the effects of heat generated by the body. Utilizing the FVM and SIMPLE scheme for pressure–velocity coupling is a good approach to investigating CBVs for five different viscosity models. In the results, it is shown that the θ and Δp+ increase with increasing Reynolds number (Re) in the CBVs. By enhancing the Re from 90 to 120 in the Cross viscosity model, the Δp+ changes about 1.391 times. The DAWSS grows by increasing the Re in all viscosity models. This increase in DAWSS leads to an increasing velocity gradient close to the cerebral vessel wall.

Heat pipes are a practical and powerful tool for recovering thermal energy and conserving energy sources. Thermosiphon is one of the most widely used devices that can transfer large amounts of heat at high rates between hot and cold sources without the use of external energy. The amount of vacuum in the pipe, the percentage of fluid filling, the type of operating fluid, the pipe’s length and the quantity of heat flux are the factors affecting the efficiency and effectiveness of the thermosiphon heat pipe. In this paper, the effects of different variables in the construction of heat pipes such as working fluid, pipe length, the use of mesh screen wick structure and the use of internal adiabatic wall on the thermosiphon heat pipes performance are investigated. The results show that using of an internal adiabatic wall eliminates and reduces limitations such as boiling, evaporator drying, thermosiphon flooding and vapor pressure and significantly improves the heat pipe’s performance. So that, the effective thermal conductivity (K) is increased up to 350% using the internal adiabatic wall. However, in some nanofluids, such as water/multi-walled carbon nanotubes (MWCNT), with increasing the nanofluid’s mass fraction, the startup speed in heat pipes with internal adiabatic wall is reduced by up to 20%.

The emergence of significant environmental problems, the depletion of fossil fuel reserves, and the anticipation of price hikes have driven researchers to explore and adopt renewable fuels derived from biological sources. Such renewable energy sources include biomass, biodiesel (BD), ethanol, bioethanol (BE), among others. Biomass is a form of energy that can be obtained from waste or the cultivation of specific plants. Notably, BD fuel can be produced from organic sources, such as animal fats or waste oil from restaurants, which is a considerable advantage of BD. Moreover, BE is a non-toxic, safe, and biodegradable fuel, and ethanol produced biologically is referred to as BE, which represents a renewable fuel with a non-fossil origin. Against this backdrop, the upcoming research employs two types of alcoholic fuel, ethanol and BD, as biomass structures. Using molecular dynamics (MD) simulation, the study evaluated the effects of temperature (Temp), pressure (Press), and external heat flux (EHF) on thermal parameters, such as HF and thermal conductivity (TC). The evaluation results indicated that an increase in the initial temperature from 1800 to 2000 K led to higher mobility of the samples, resulting in an increase in the values of HF and TC from 488 to 551 W/m2 and 0.26–0.32 W/m.K, respectively. Similarly, raising the initial Press from 1 to 5 bar increased the number of oscillations and mobility of the structures, leading to increased HF and TC values from 488 to 551 W/m2 and 0.26–0.32 W/m.K, respectively. Notably, the EHF changes exhibited similar behavior. Additionally, a significant outcome was observed when the EHF rose from 1 to 5 W/m2. This increase in EHF led to a corresponding rise in the number of reactions occurring in the studied structure. As a result, the released heat intensified, leading to increased HF and TC values. Specifically, HF values rose from 503 to 538 W/m2, and TC increases from 0.28 to 0.31 W/m.K.

In this work, a two-phase simulation is used to examine the flow of nanofluid and hydraulic-thermal analysis in a tube with triple-perforated twisted tape (TT). Water-MWCNT NF is used as the heat transfer fluid (HTF) in a variety of volume concentrations (φ). The fluid enters the tube at Tin = 300 K at different velocities corresponding to Reynolds numbers 6000, 12000, 18000, and 24000. The 2L inlet-to-length section is intended to confirm that the inlet flow is entirely developed. In this work, various geometrical factors of TT are investigated. The optimization is carried out to achieve the utmost PEC. According to the results, the use of TT has a profound effect on the H-T features of the channel and causes undulating flow, which increases the heat transfer (HT) coefficient and the pressure drop (Δp). Besides, it is recognized that the PEC values are always greater than 1.10, indicating that the utilization of these turbulators (TRBs) is H-T efficient. The perforated pattern (Case E and N = 4) is presented as the best pattern in this study, and its PEC amounts for NF in φ = 0.8% at Re = 6000, 12000, 18000, and 24000 are 1.38, 1.60, 1.77, and 1.92, respectively.

The present study numerically investigated the simulation of two-phase nanofluid (NF) flow to examine the thermal performance of Cu–water NF within an enhanced tube with W- and C-shaped ribs in the heat exchangers (HEX). In this research, the effect of volume fraction (φ = 0.2, 0.4, 0.6, and 0.8%), and diameter (15, 20, 25 and 30 nm) of copper nanoparticles and the type and size of the turbulators (TRB) (W- and C-shaped ribs together), which were designed for the first time on Heat transfer (HT), were discussed. Heat transfer flow (HTF) entered the test section at Tin = 290 K in various velocities related to different Reynolds numbers (Re) 5000, 10000, 15000 and 20000. Based on the Eulerian-Eulerian two-phase method, the governing equations were solved. Different rib geometrical parameters were determined, and the optimization was performed to achieve the maximum performance evaluation criteria (PEC). According to obtained results, the PECs were more than 1, which indicated that these TRB were impressive from a hydraulic-thermal performance. Furthermore, the PEC variations of C- and W-shaped models were not similar. For the C-shaped configuration, the PEC values always enhanced with Re enhancement, while for the W-shaped model, the PEC values enhanced till Re = 10000, and then decreased till Re = 20000. The PEC values of the optimum model (W-shaped, NB = 6 and R = 15 mm) filled by NF at φ = 0.8% and dnp = 30 nm in Re = 5000, 10000, 15000 and 20000 are 1.491, 1.498, 1.482 and 1.469, respectively.

In this study, the thermal conductivity (knf) of ZnO -TiO2 (50 %–50 %)/ Ethylene Glycol hybrid nanofluid using Artificial Neural Networks (ANNs) was predicted. The nanofluid was prepared at different volume fractions (φ) of nanoparticles (φ = 0.001 to 0.035) and temperatures (T = 25 to 50 °C). In this study, an algorithm is presented to find the best neuron number in the hidden layer. Also, a surface fitting method has been applied to predict the knf of nanofluid. Finally, the correlation coefficients, performances, and Maximum Absolute Error (MAE) for both methods have been presented and compared. It could be understood that the ANN method had a better ability in predicting the knf of nanofluid compared to the fitting method. This method not only showed better performance but also reached a better MAE and correlation coefficient.

Numerous theoretical and experimental studies were conducted on thermal energy storage utilizing phase change materials (PCMs). This study employs paraffin with particular properties as the PCM in a square solar water heater. Paraffin's melting point (MP) is 55 °C, the flow is transient, and natural convection is responsible for the heat transfer (HT). In this study, the effect of fin geometry, such as height (H) (3, 4, and 5 cm), and the number of fins (NoF) (double and triple), on the performance of the heat exchanger (HE) was investigated. For various parameters, temperature (T) and liquid fraction contours were produced. The results show that, the melting time (MT) for case A (without fins) about 3860 s. Based on the calculations, the reduction of MT for case B (with 3 fins) is 71%. The MT reduction at H=3, 4, and 5 cm equal to 48, 61, and 74% respectively.

Phase change materials (PCMs) are well known for their inherent poor thermal characteristics, which consequently results in limited thermal efficiency for thermal energy storage systems (TESS). The current work numerically attempts to improve the thermal efficiency of TESS by employing Y-shaped fins with nano-enhanced PCM (NePCM). The NePCM is contained inside the cylindrical TESS, while water, as heat transfer fluid (HTF), is pumped through inner pipes. Three different configurations of the TESS were studied and compared; case 1: the reference case (with no fins), case 2: with two Y-shaped fins attached to the tubes, and case 3: with four Y-shaped fins attached to the tubes. The finite element method is employed to discretize the system's governing equations. Besides the influence of the TESS configuration, the impact of HTF temperature (338 and 348 K) and the volume fraction of the nanoparticles (0–0.08) were also addressed. The evolution of temperature contours and liquid fraction of the three different configurations under the two different HTF temperatures are discussed and analyzed. The findings revealed that using nanoparticles with 8 vol% enhanced the thermal conductivity during melting by 19%. The melting process was accelerated by 87% when the HTF temperature was higher (348 K). Finally, TESS with four Y-shaped fins was found to be the most effective as it achieved a 48% melting time reduction compared to the base case (case 1).