Davood Toghraie

• Professor
• Professor (Associate) at Islamic Azad University of Khomeynishahr

This study uses molecular dynamics simulations to examine the effects of different external magnetic field frequencies on the atomic and thermal properties of a paraffin/copper composite in a tube with rotating ribs. A stable starting state was first achieved via a 10-ns equilibration phase, which produced a temperature of 300 K and kinetic and pot...

This study examines the thermal properties of phase change materials (PCMs) using molecular dynamics simulation, concentrating on a cylindrical system including octadecane and water as PCMs. The study was executed in two phases: atomic structure equilibration and thermal analysis. During equilibration, the system's potential and total energy reache...

The study investigated the effects of Sr-doping on BaTiO₃ regarding the mean square displacement, diffusion coefficient, polarization-strain response, dielectric constant, and dielectric loss. Initially, increasing strontium doping up to 6% enhanced the mean square displacement (from 0.211 to 0.218 Ų) and the diffusion coefficient (from 0.361 to 0...

Improving heat transfer is an extremely significant case in industries such as coolers, solar collectors, heat exchangers and nuclear reactors. Therefore, thermo-physical properties can become progressed by using suitable NFs. During this laboratory checking, after preparing a special and economical type of water–based NF, its thermal conductivity...

It is essential to adopt new technologies to meet the growing demand for freshwater. Among the methods for removing dissolved salts, reverse electrodialysis stands out as a promising membrane-based solution for desalination. This study used molecular dynamics simulations to examine how carbon nanotube permeability, particle diffusion, and channel g...

This study numerically investigated the enhancement of micromixing efficiency through integrating surface acoustic waves (SAWs) and hyper-elastic channel walls, modeled using a power-law fluid representative of human blood flow. The governing equations are systematically divided into zeroth, first, and second orders based on perturbation theory. Th...

In the present paper, ANNs with different neurons considering T and SVF of nanoparticle parameters were applied to evaluate the test set for TC of MWCNT-ZnO (15:85)/EG nanofluid. Nanofluid data were evaluated at SVF = 0.055–1.85% and T = 28–55 °C. MLP ANN with LM training algorithm was applied. MOD versus all ANN data (TCR) is in the range between...

In this study, thermophysical properties of MWCNT (15%)-ZnO (85%)/ethylene glycol hybrid nanofluid (HNF) have been investigated statistically and experimentally. Understanding thermal behavior of nanofluid (NF) in different laboratory conditions and also determining the correlation between process factors and how the factors affect the thermal beha...

Managing the heat generated in microprocessors and other similar heat-generating devices requires the design and construction of superconductors with high reliability. For this purpose, heat pipes (HPs) are a very good option. Nano-grooved micro flat plate heat pipes (FPHPs), which are in the group of vapor chambers (VCs), have received attention d...

This study investigated the piezoelectric properties of BaTiO3 ceramics with different sizes through molecular dynamics simulations. The results show that all samples reached thermal equilibrium at 300 K and equilibrium in potential energy within 10 ns, confirming effective equilibration. As the size of the ceramics increased, the mean square displ...

Recently, a great deal of study was done on the rheological characteristics and heat transfer of nanofluids (NFs). This study investigated how temperature and solid volume fraction (SVF) parameters affected the dynamic viscosity of water hybrid nanofluids (HNF), and zirconium oxide (ZrO2)–tungsten oxide (WO3)–MWCNTs (MWCNTs). Binary HNF combination...

Bioceramics composed of calcium and magnesium silicates have garnered increasing attention for the development of porous scaffolds in bone tissue engineering (BTE). This heightened interest is primarily attributed to their remarkable bioactivity and their capacity to form strong bonds with hard tissue. Fabricating nanocomposite scaffolds is a recog...

Certain materials (ceramics and polymers) are capable of converting mechanical energy into electrical energy via the piezoelectric effect. The piezoelectric effect is fundamentally associated with momentary electric dipoles that occur in solids. The external surface may be borne directly by molecular groups or excited in the crystal lattice by an a...

In the present research, after preparing a new generation of SWCNT–Fe3O4–CuO/ethylene glycol (EG)–water ternary hybrid nanofluid (THNF), the thermal conductivity (TC) and its effective factors (solid volume fraction (SVF) and temperature (T)) are studied. Results show that the increase in T and SVF has a very favorable effect on the process of opti...

This study used molecular dynamics simulation to investigate how temperature changes the piezoelectric properties of crystal barium titanate in its tetragonal form. Consistent with the results, the oxygen diffusion coefficient in the simulated sample increased to 0.35 Å2/ns (expansion mode) and 0.56 Å2/ns (contraction mode) by increasing the temper...

In this study, the dynamic viscosity (\({\mu }_{{\text{nf}}})\) of oil-based hybrid nanofluid (NF) containing MWCNTs nanoparticles (NPs) was investigated using the artificial neural network (ANN) method at temperatures from 5 to 55 \(^\circ{\rm C}\), volume fractions from \(\varphi =\) 0.0625 to 1%, and different shear rates (SRs). One of the advan...

In the present study, for the first time, the production rate of freshwater by hemispherical solar desalination still with two salty water basins is investigated. For this purpose, two-dimensional modeling of solar desalination is performed, and the effects of different and independent temperatures for salty water basins on evaporation rate and ave...

One of the common methods is the molecular dynamics simulation which models the behavior of atoms and molecules. This paper used the molecular dynamics technique to simulate the behavior of SARS-COV-2 virus under variable heat flux conditions. By doing so, it can be observed how the virus structure responded to the changes in external heat flux and...

As the transport sector is responsible for the consumption of a vast proportion of the oil produced, it is mandatory to research feasible solutions to tackle this issue. The application of aerodynamic attachments for passive flow control and reducing resisting aerodynamic forces such as drag and lift is one of the most practicable ways to minimize...

This research studied the effect of initial temperature (300-400K), and atomic percentage of toluene catalyst (1-10%) on the atomic and thermal performance of air/methane catalytic combustion. The present study was performed using molecular dynamics (MD) simulation. The results demonstrate that by increasing the initial temperature from 300 to 400...

1) Background: Phase change materials (PCMs) have been used statically, which has caused the use of these materials to face challenges. Encapsulating PCMs and combining them with the base fluid can significantly solve the problem of using PCMs in BTM systems. In the present study, based on computational fluid dynamics, forced convection heat transf...

Managing the heat generated in equipment such as microprocessors requires optimal thermal design. As a type of superconductor, heat pipes (HPs) are a suitable choice for this purpose. The performance of micro-HPs can be affected by the body material and working fluid, among other parameters. The present paper examines the use of a nanofluid inside...

The aim of this article is an empirical investigation of the MWCNT and ZnO (30:70)/10W40 HNF against SR, SVF, and T. In this study, the nanoparticles (NPs) are examined with SVF = 0.05%-1% and T = 5–55 °C. After adding NPs to 10W40 engine oil, non-Newtonian behavior is observed. Optimizing the viscosity behavior of NF is another goal of this study,...

In this study, optimization of ZnO/EG nanofluids was investigated to increase efficiency and reduce costs. To determine the efficiency of nanofluid, the definition of Mouromtseff number was used. The cost of nanofluid in terms of the volume fraction of nanoparticles (φ) was determined. Then, Mouromtseff functions and costs were calculated by respon...

This investigation aimed to evaluate the thermal conductivity ratio (TCR) of SWCNT-CuO/Water nanofluid (NF) using experimental data in the T range of 28–50 ℃ and solid volume fraction range of SVF = 0.03 to 1.15% by an artificial neural network (ANN). MLP network with Lundberg-Marquardt algorithm (LMA) was utilized to predict data (TCR) by ANN. In...

Phase change materials (PCMs) are capable of thermal energy storage since they have a set melting point and a high latent heat of melting. PCMs offer up to 15 times the heat capacity per unit volume compared to conventional storage materials. The results show that laboratory methods were expensive and time-consuming. Therefore, using the molecular...

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...

The present paper examines turbulent flow and heat transfer characteristics of a three-dimensional laterally perforated finned heat sink (LPFHS) using response surface methodology (RSM) and computational fluid dynamics (CFD) approaches. The effects of the Reynolds number and perforations geometry, such as porosity (size) and cross-sectional shape (...

In current computational research, the effect of Polycaprolactone (PCL) coating on the mechanical properties (MP) of biomimetic calcium phosphate (BCP)/Baghdadite (BG)-AK nanocomposite (NC) is investigated by using molecular dynamics simulation (MDS). Our study models BCP/BG-AK-PCL samples by Universal Force Field (UFF) and DREIDING potential funct...

This study investigates lead (II) removal using grapevine leaf and polypyrrole composites. Batch adsorption tests were performed in the presence of lead (II) solutions and the selected adsorbent at different pH, initial concentration of the metal ion, contact time, and adsorbent dosage. The properties of the composites were characterized by X-ray d...

This paper investigates the impact of Solid Volume Fraction (SVF) and temperature on the dynamic viscosity of a hybrid antifreeze composed of MWCNTs and aluminum oxide in a mixture of water (80%) and ethylene-glycol (20%). An Artificial Neural Network (ANN) is used to predict the viscosity of the nanofluid, which was generated at different SVFs ran...

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 pape...

The main goal of this research is to compare the rheological behavior of hybrid nano lubricants (HNLs) with different composition ratios in a base oil. The purpose of the comparison is to determine the HNL with the best lubrication performance at the start of the vehicle. Theoretical methods have confirmed the non-Newtonian behavior in different la...

The increase in demand for water has caused attention to non-traditional methods for water supply in many places. Solar still is a simple, economical and suitable technology for providing drinking water from salt water that can be used even in remote areas. The challenge facing these technologies is to increase their performance, which is possible...

Multiple network hydrogels are the most widely used materials in biomedical applications due to their optimal biological properties and tunable physical characteristics. Herein, we develop an innovative aqueous‐based synthesis of a novel triple-network Gelatin/Polyacrylamide/Carboxymethyl chitosan hydrogel. Triple-network hydrogel was synthesized b...

This work studies the mechanical behavior of double-walled carbon nanotubes (DWCNTs) under temperature gradients and electrical fields based on the nonlocal reddy beam model, focusing on the free vibration of DWCNTs. The DWCNTs include the interaction of van der Waals (vdW) forces between the outer and inner tubes, and they are supposed to be embed...

Background: Global warming and the human need for power resources in the last decades have highlighted the concerns related to energy saving for long-term applications. Thermal energy-saving systems are an important technique to overcome this issue. Methods: In the present study, we aim to simulate the performance of a thermal energy-storing sys...

The use of substandard nanofluids (NFs) in various industries causes the depreciation of industrial parts and shortens the life of the parts. Therefore, the researchers in this study will help to improve the performance of industrial equipment by preparing and examining a special hybrid nanofluid (HNF). The current research is divided into two expe...

A comprehensive three-dimensional finite element of the superstructure foundation model includes the effect of lots of important parameters on the structure performance. Among these parameters, rigidity and flexibility of raft foundations and soil interactions become an important aspect of design due to their efficient, practical and economic perfo...

Graphene is a two-dimensional material with excellent mechanical, electrical, and thermal properties made up of single layers of carbon atoms. Despite the fact that graphene is an emerging material, nowadays graphene has become the leader of the nano field, and with the discovery of its various properties, a tremendous transformation is taking plac...

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...