Araştırma Çıktıları | WoS | Scopus | TR-Dizin | PubMed
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Publication Metadata only Changes in mechanical properties of copper-silver matrix welded by the iron blade by increasing initial pressure: A molecular dynamics approach(ELSEVIER, 2024) Ayadi, Badreddine; Jasim, Dheyaa J.; Sajadi, S. Mohammad; Nasajpour-Esfahani, Navid; Salahshour, Soheil; Esmaeili, Shadi; Sabetvand, Rozbeh; Elhag, Ahmed Faisal Ahmed; University Ha'il; Universite de Sfax; Ecole Nationale dIngenieurs de Sfax (ENIS); Al-Amarah University College; Cihan University-Erbil; University System of Georgia; Georgia Institute of Technology; Okan University; Lebanese American University; Bahcesehir University; Semnan University; Amirkabir University of Technology; Qassim UniversityAtomic 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.Publication Metadata only Influence of graphene nanoplate size and heat flux on nanofluid heat exchanger performance: A molecular dynamics approach(PERGAMON-ELSEVIER SCIENCE LTD, 2025) Yang, Zhongxiu; Basem, Ali; Jasim, Dheyaa J.; Singh, Narinderjit Singh Sawaran; Saeidlou, Salman; Al-Bahrani, Mohammed; Sajadi, S. Mohammad; Salahshour, Soheil; Hasanabad, Ali Mohammadi; Weifang University of Science & Technology; University of Warith Alanbiyaa; Al-Maarif University; INTI International University; Canterbury Christ Church University; Al-Mustaqbal University College; Okan University; Bahcesehir University; Ministry of Education of Azerbaijan Republic; Khazar UniversityThis study aimed to enhance the thermal efficiency of nanofluid-based heat exchangers by exploring the simultaneous effects of external heat flux and graphene nanoplate sizes on thermal and structural characteristics. Effective heat transfer is a critical requirement for managing heat in microscale systems, where optimizing the thermal performance of nanofluids can improve device performance. Molecular dynamics simulations were carried out of a sinusoidal inner surface copper heat exchanger coated with silicon nanoparticles to demonstrate atomic-level interaction within the nanofluid. The significant findings showed that while an external rising heat flux decreased heat flux from 41.7 to 37.26 W/m2 and thermal conductivity of nanofluid from 14.53 to 13.80 W/ m & sdot,K, only an increase in viscosity from 0.32 to 0.49 mPa & sdot,s, the agglomeration time of nanoparticles decreased from 3.71 to 3.33 ns and friction coefficient from 0.022 to 0.015, could indicate a difference in particle behavior responding to the thermal stress. However, the size of the graphene nanoplate from 5 to 15 & Aring, increases the heat flux from 40.05 to 46.77 W/m2 and thermal conductivity of the nanofluid from 14.15 to 14.99 W/m & sdot,K, since the larger graphene nanoplate films can produce a more substantial covalent bonding and link interlayer coupling. In contrast, the larger nanoplate also enhanced viscosity from 0.30 to 0.39 mPa & sdot,s, aggregation time from 3.64 to 4.01 ns, and friction coefficient from 0.020 to 0.026, which indicated lower particle mobility. This study was the first of its kind to contribute to the existing knowledge gap by investigating the simultaneous effect of both the nanoplate size and external heat flux in an oscillating microchannel heat exchanger. The knowledge provided offers an experimental pathway in optimizing the nanofluid properties and the heat exchanger geometry for improved thermal management for compact and microscale applications.Publication Metadata only Molecular dynamics simulation of mechanical and oscillating characteristics of graphene nanosheets with zigzag and armchair edges(ELSEVIER, 2024) Fei, Qiang; Al-dolaimy, F.; Sajadi, S. Mohammad; Alawadi, Ahmed Hussien; Haroon, Noor Hanoon; Jasim, Dheyaa J.; Salahshour, Soheil; Alsaalamy, Ali; Eftekhari, S. Ali; Hekmatifar, Maboud; Guangdong University of Science & Technology; Al-Zahraa University for Women; Cihan University-Erbil; Islamic University College; Islamic University College; University of Babylon; Al-Ayen University; Al-Amarah University College; Okan University; Bahcesehir University; Lebanese American University; Imam Jaa'far al-Sadiq University; Islamic Azad UniversityAn oscillator is a circuit that can produce a continuous, repetitive, and alternating waveform without any input. However, the oscillations caused by the conversion between the two forms of energy cannot last forever. As a result, the amplitude decreases until it becomes zero, thus causing their nature to decrease. After discovering graphene nanosheets, their use in nanoelectricity science was much considered. Due to the amazing properties of graphene nanosheets, they can be used to establish permanent oscillations. The results show that graphene nanosheets ' mechanical properties and electrical properties depend on their structure and shape. Therefore, this study investigates the effect of graphene nanosheets type, size, and temperature on the simulated nanostructure's mechanical properties and oscillating behavior with Molecular Dynamics simulation. The results show that the graphene nanosheets with zig-zag edges has higher mechanical strength than armchair edges. Young's modulus and Ultimate strength of graphene nanosheets with zig-zag edges are numerically 1079 and 115 GPa, respectively. On the other hand, the resistance in graphene nanosheets can be expressed by reducing the oscillation amplitude and increasing the oscillation frequency. The results show that by changing the armchair edges to zigzag, the oscillation amplitude of graphene nanosheets decreases from 10.36 to 9.82 angstrom. Also, by enhancing the length of graphene nanosheets from 30 to 100, the oscillation amplitude of graphene nanosheets increases from 7.59 to 12.12 angstrom. This increase is due to the increases in the contact surface of the atomic structures. Consequently, the interactions between the carbon particles and mechanical resistance decrease. According to the results of this project, the findings improve the dynamics of nanoscale oscillators and cause a significant improvement in the performance of various devices.Publication Metadata only The effect of initial conditions (temperature and pressure) on combustion of Fe-coated-aluminum hydride nanoparticles using the molecular dynamics approach(ELSEVIER, 2024) Yuanlei, Si; Hammoodi, Karrar A.; Sajadi, S. Mohammad; Rashid, Farhan Lafta; Li, Z.; Jasim, Dheyaa J.; Salahshour, Soheil; Esmaeili, Shadi; Sabetvand, Rozbeh; Jiangsu Vocational Institute of Architectural Technology; University of Warith Alanbiyaa; Cihan University-Erbil; University of Kerbala; Donghai Laboratory; Opole University of Technology; Al-Amarah University College; Okan University; Bahcesehir University; Lebanese American University; Semnan University; Amirkabir University of TechnologyHighly combustible elements like beryllium, lithium, Al, Mg, and Zn have the highest combustion, increasing the heat in explosives and propellants. Al can be used because of its greater avail-ability. Reducing the size of Al nanoparticle (NP) increases the combustion rate and decreases the combustion time. This paper studied the effect of initial conditions on the phase transition (PT) and atomic stability times of Fe-coated-aluminium hydride (AlH3) NPs. The molecular dynamics (MD) technique was used in this research. The microscopic behavior of structures was studied by density (Den.), velocity (Vel.), and temperature (Tem.) profiles. Heat flux (HF), PT, and the atomic stability of the structure were examined at different initial pressures (IP) and initial temperatures (IT). According to the achieved results, Den., Vel., and Tem. values had a maximum value of 0.025 atoms/angstrom 3, 0.026 angstrom/ps, and 603 K. By increasing IT in the simulation box to 350 K, HF in the samples increases to 75.31 W/m2. Moreover, the PT time and atomic stability time by increasing IP reach to 5.93 ns and 8.96 ns, respectively. Regarding the importance of the phe-nomenon of heat transfer and PT of nanofluids (NFs), the findings of this study are predicted to be useful in various industries, including medicine, agriculture, and others.Publication Metadata only Numerical examination of exergy performance of a hybrid solar system equipped with a sheet-and-sinusoidal tube collector: Developing a predictive function using artificial neural network(ELSEVIER, 2024) Sun, Chuan; Fares, Mohammad N.; Sajadi, S. Mohammad; Li, Z.; Jasim, Dheyaa J.; Hammoodi, Karrar A.; Nasajpour-Esfahani, Navid; Salahshour, Soheil; Alizadeh, As'ad; Huanggang Normal University; University of Basrah; Cihan University-Erbil; Donghai Laboratory; Opole University of Technology; Al-Amarah University College; University of Warith Alanbiyaa; University System of Georgia; Georgia Institute of Technology; Okan University; Bahcesehir University; Lebanese American University; Urmia UniversityIntegrating 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 (omega) from 0 % to 1 % increased the useful thermal exergy and overall exergy efficiency (Exu,t/ Yov) 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/ Yov exhibited a reducing trend at Re = 2000, 0.3928 %/0.1056 % decrease. In addition, the increase in omega from 0 % to 1 % caused the useful electricity and electrical exergy (Exu,e/ Ye) 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, Ye, and Yov by 60 %, 1.26 %, 1.26 %, and 17.50 %, respectively, at different omega 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 omega). The results showed high accuracy of the proposed model with MSE, EMSE, and R2 of 0.0138, 0.1143, and 0.99785, respectively.Publication Metadata only Combining neutral scalar and isothermal Shan-Chen lattice Boltzmann method to simulate droplet placement on a wall in isothermal and non-isothermal states(ELSEVIER, 2024) Liu, Yanan; Jasim, Dheyaa J.; Sajadi, S. Mohammad; Nasajpour-Esfahani, Navid; Salahshour, Soheil; Zarringhalm, Majid; Rahmani, Amin; Al-Amarah University College; Cihan University-Erbil; University System of Georgia; Georgia Institute of Technology; Okan University; Bahcesehir University; Lebanese American University; Islamic Azad University; University of ExeterBackground: In the current article, two-phase thermal fluxes are created by combining the thermal model of the neutral scalar model with the two-phase Shan-Chen model of the lattice Boltzmann method (LBM). Methods: The different intermolecular powers for the isothermal Shan-Chen model show how a droplet would be placed on a wall. By raising the droplet intermolecular power parameter, the surface area increases and becomes wet. Next, the isothermal Shan-Chen method and the neutral scalar method are combined to investigate multiphase thermal problems. The droplet placement on the hot wall is therefore done at relatively high Rayleigh numbers. By raising the Rayleigh number, the isothermal lines within the droplet's interior gradually become less ascending and less descending until they eventually achieve a uniform state when it is placed against a hot wall. Additionally, the channel's Rayleigh-Benard convective heat transfer is enhanced by increasing the Rayleigh number. Significant findings: Natural convection in the enclosures can be used in solar collectors. As the Rayleigh number increases, the average Nusselt number (Nuavg) rises as would be expected. The results demonstrate that LBM is a practical method for simulating multi-phase thermal flows.Publication Metadata only Preparation and identification of a novel 1,1′-(1,4-phenylenebis (methylene) bis (4-cyanopyridin-1-ium) bromide as a corrosion inhibitor for C1018 in highly acidic media(ELSEVIER, 2024) Kuraimid, Zaidoun K.; Fouda, Abd El-Aziz S.; Sajadi, S. Mohammad; Abid, Dawood S.; Wahba, A. M.; Jasim, Dheyaa J.; Salahshour, Soheil; Egyptian Knowledge Bank (EKB); Mansoura University; University of Basrah; Basrah University College of Science and Technology; Cihan University-Erbil; Al-Amarah University College; Okan University; Bahcesehir University; Lebanese American University1,1 '-(1,4-phenylene-bis (methylene)) bis(4-cyanopyridin-1-ium) bromide (PCB) was synthesized and identified via spectral methods: Fourier-transform infrared (FTIR) spectroscopy, proton nuclear magnetic resonance hydrogen (1HNMR), and proton nuclear magnetic resonance carbon (13CNMR). The inhibitory effect (% IE) was determined using weight loss (WL) method, potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) techniques for the corrosion of C1018 in strong (6 M) HCl. % IE reached 98.9 % at 200 mg/L, 313 K. The effects of the PCB concentration, HCl concentration, and temperature on the corrosion rate of C1018 were then confirmed using WL. The PDP curves indicate that PCB acts as mixed type- inhibitor. The adsorption of PCB obeyed the Langmuir adsorption isotherm. The adsorption of PCB on C1018 revealed that the adsorption process exhibiting physical and chemical adsorption. Theoretical modeling revealed the correlation between the QAS molecular chemical structure and its anticorrosive property. All the experimental and theoretical calculations were in good agreement.Publication Metadata only The nano-pumping process of C20 molecules from carbon nanotube at the different external electric fields and atomic defects: A molecular dynamics approach(ELSEVIER SCIENCE SA, 2024) Niu, Haichun; Rasheed, Rassol H.; Sajadi, S. Mohammad; Jasim, Dheyaa J.; Salahshour, Soheil; Nasajpour-Esfahani, Navid; Sabetvand, Rozbeh; University of Warith Alanbiyaa; Cihan University-Erbil; Al-Amarah University College; Okan University; Bahcesehir University; Lebanese American University; University System of Georgia; Georgia Institute of Technology; Amirkabir University of TechnologyToday, carbon nanotubes are involved in many medical types of research, such as biosensors and drug delivery. These nanotubes do not pose a problem for the body regarding toxicity to body cells and triggering the immune system. Nanotubes have also been proven to increase solubility and the possibility of targeted drug delivery. This study used molecular dynamics simulation to examine the nano-pumping process of the C20 molecule in carbon nanotubes at the different electric fields and atomic defects. The process of C20 molecule nano-pumping was examined by examining the changes in kinetic energy, potential energy, entropy, stress, temperature, and in-ternal energy changes. In the following, the stress on the atomic structure was calculated. For this purpose, constant electric fields with the magnitudes of 0.01, 0.02, 0.03, 0.05, and 0.1 V/angstrom are used for the atomic structure. The results show that the nano-pumping time of the C20 molecule in the carbon nanotubes increases by increasing the electric field magnitude. The results also revealed that the kinetic energy in the structure decreased by increasing the electric fields, and the potential energy increased. As the potential energy increased in the atomic structure, the stability increased. Therefore, it is expected that the C20 molecule nano-pumping time will increase. The following examined the effect of atomic defects in an electric field with a magnitude of 0.01 V/angstrom. For this purpose, the atomic defects with magnitudes of 1 %, 2 %, 3 %, and 4 % were used for carbon nanotubes. The results revealed that increasing the atomic defects increased the C20 molecule nano-pumping time. Furthermore, the stress on the structure increased by increasing the atomic defects.Publication Metadata only Obtaining an accurate prediction model for viscosity of a new nano-lubricant containing multi-walled carbon nanotube-titanium dioxide nanoparticles with oil SAE50(ELSEVIER SCI LTD, 2024) Zhang, Yuelei; Hammoodi, Karrar A.; Sajadi, S. Mohammad; Li, Z.; Jasim, Dheyaa J.; Nasajpour-Esfahani, Navid; Salahshour, Soheil; Eftekhari, S. A.; Khabaz, Mohamad Khaje; Wuchang University of Technology; University of Warith Alanbiyaa; Cihan University-Erbil; Donghai Laboratory; Opole University of Technology; Al-Amarah University College; University System of Georgia; Georgia Institute of Technology; Okan University; Bahcesehir University; Lebanese American University; Islamic Azad UniversityThis study aims to investigate the viscosity behavior of multi-walled carbon nanotube (MWCNT) - titanium dioxide (TiO2) (40-60) - SAE50 oil nanofluid using an Artificial Neural Network (ANN) modeling approach. The main objective is to develop a highly accurate predictive model for viscosity by considering three input parameters: temperature, solid volume fraction (SVF), and shear rate (SR). Rheological measurements provide experimental data used to train and validate the ANN model. The ANN model's architecture, activation functions, and training algorithms are carefully chosen. Data are divided to three subsets including train, validation and test. ANN is trained using trainlm algorithm for 50 times to vanish the effect of random nature of ANN weight initialization. The trained ANN model is then utilized to predict the viscosity of the nanofluid under varying conditions. The results demonstrate the efficacy of the proposed ANN model in capturing the complex relationship between viscosity and the input parameters, providing accurate viscosity predictions for the MWCNT-TiO2-oil SAE50 nanofluid. Furthermore, the influence of temperature, SVF, and SR on viscosity is analyzed, offering valuable insights into the flow behavior of the nanofluid. According to the obtained results, the developed ANN model presents a reliable and efficient approach to estimate the viscosity of the MWCNTTiO2-SAE50 oil nanofluid, eliminating the need for costly and extensive experimental measurements within the analyzed range. ANN could model the nanofluid viscosity with R2 = 0.9998 and MSE= 0.000189 that is quite acceptable. Also, the experimental data revealed that for the investigated nanofluid, temperature and shear rate have impressive effect on the viscosity (changing viscosity more than 100% for the analyzed margin), on the other hand, the nanoparticle volume fraction effect is much lower, to be more precise, increasing the nanoparticle percentage will increase the viscosity mean value around 30%.Publication Metadata only The effect of initial pressure on the thermal behavior of the silica aerogel/PCM/CuO nanostructure inside a cylindrical duct using molecular dynamics simulation(ELSEVIER, 2024) Gao, Yuanfei; Basem, Ali; Sajadi, S. Mohammad; Jasim, Dheyaa J.; Nasajpour-Esfahani, Navid; Salahshour, Soheil; Esmaeili, Shadi; Baghaei, Sh.; Nanyang Normal College; University of Warith Alanbiyaa; Cihan University-Erbil; Al-Amarah University College; University System of Georgia; Georgia Institute of Technology; Okan University; Bahcesehir University; Lebanese American University; Semnan University; Islamic Azad UniversityAmidst 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/angstrom 3 to 0.0852 atom/angstrom 3, and the maximum velocity decreases from 0.0091 angstrom/fs to 0.0081 angstrom/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.
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