An approach to develop a digital twin for industry 4.0 systems: manufacturing automation case studies

The new paradigm of digital manufacturing and the concept of Industry 4.0 has led to the integration of recent manufacturing advances with modern information and communication technologies. Therefore, digital simulation tools fused into production systems can improve time and cost-effectiveness and enable faster, more flexible, and more efficient processes to produce higher-quality goods. The advancement of digital simulation with sensory data may support the credibility of production systems and improve the efficiency of production planning and execution processes. In this paper, an approach is proposed to develop a Digital Twin of production systems in order to optimize the planning and commissioning process. The proposed virtual cell interacts with the physical system with the help of different Digital Manufacturing Tools (DMT), which allows for the testing of various programs in a different scenario to check for any shortcomings before it is implemented on the physical system. Case studies from the different production systems are demonstrated to realize the feasibility of the proposed approach

Natural convection of rectangular cavity enhanced by obstacle and fin to simulate phase change material melting process using Lattice Boltzmann method

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

Entropy analysis and mixed convection of nanofluid flow in a pillow plate heat exchanger in the presence of porous medium

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

Simulation the effect of capply layer length on the longitudinal stiffness and lateral stiffness of the tire and the stability of the car

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 %

The effect of initial pressure on the thermal behavior of the silica aerogel/PCM/CuO nanostructure inside a cylindrical duct using molecular dynamics simulation

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

Tribological characterization of laminated hybrid AA1050/TiC/Graphite composite bars

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 effect of different variables and using of the internal adiabatic wall in the construction and performance of thermosiphon heat pipes: Experimental investigation

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%

A new model for viscosity prediction for silica-alumina-MWCNT/Water hybrid nanofluid using nonlinear curve fitting

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

Effect of Y-shaped fins on the performance of shell-and-tube thermal energy storage unit

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)

Bonding evolution of composites fabricated via electrically assisted press bonding

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