Papers by Marjan Goodarzi
Mathematics, 2021
PTSCs (parabolic trough solar collectors) are widely employed in solar-thermal applications to at... more PTSCs (parabolic trough solar collectors) are widely employed in solar-thermal applications to attain high temperatures. The purpose of this study is to determine how much entropy is created when Powell-Eyring nanofluid (P-ENF) flows across porous media on a horizontal plane under thermal jump circumstances. The flow in PTSC was generated by nonlinear surface stretching, thermal radiation, and Cattaneo-Christov heat flux, which was utilized to compute heat flux in the thermal boundary layer. Using a similarity transformation approach, partial differential equations were converted into ordinary differential equations with boundary constraints. Then, the boundary restrictions and partial differential equations were merged to form a single set of nonlinear ordinary differential equations. To obtain approximate solutions to ordinary differential equations, the Keller-Box approach is utilized. Nanofluids derived from silver- and copper-based engine oil (EO) has been employed as working f...
Journal of Thermal Analysis and Calorimetry, 2020
The efficiency of electronic equipment is the cornerstone of technology development. Thermal cond... more The efficiency of electronic equipment is the cornerstone of technology development. Thermal conditions significantly affect the performance of electronic components. Moreover, mechanical strength, size, and mass are the parameters that impose some limitations. Thus, they should be considered in the high tech industry. Therefore, it is needed to examine both mechanical and thermal behaviors simultaneously. Microchannel and inserted high-conductivity materials are two usual cooling approaches. To improve cooling efficiency and mechanical strength, a new method named Hybrid is introduced here. This method is a combination of microchannel and high-conductivity methods. In this study, the consumed energy, the conductivity ratio of the material with high conductivity, peak temperature, and maximum Von Mises stress have been investigated and analyzed. For the hybrid method, the peak temperature and stress were minimized regarding the volume of high-conductivity change in the tangential direction of the duct. The results showed that the tangential hybrid method could decrease the peak temperature and peak Von Mises stress, up to 40% and 34% in comparison to the microchannel and high-conductivity inserts method.
Applied Sciences, 2021
A set of lab-scale experiments were designed and conducted to remedy Direct Blue 15 (DB15) dye us... more A set of lab-scale experiments were designed and conducted to remedy Direct Blue 15 (DB15) dye using nontoxic halloysite nanotubes (HNT) with the view to be utilized in a textile industrial effluent (TIE). The DB15 adsorbed-HNT “sludge” was used as a reinforcing agent and plastic waste to fabricate the composite. To advance the knowledge and further understand the chemical phenomena associated with DB15 adsorption on HNT, different factors like pH value, adsorbate initial concentration, adsorbent dosage, and temperature on the composite were affected experimentally tested. To estimate the adsorption capacity of HNT, nine isotherm models were applied, and it was identified that the Brouers–Sotolongo adsorption isotherm model represented the best accuracy for predicting the adsorption behavior of the HNT. Likewise, the pseudo-second-order reaction was the predominant mechanism for the overall rate of the multi-step dye adsorption process. Additionally, it was demonstrated that the mas...
Symmetry, 2020
The present investigation is directed towards synthesis of zinc oxide (ZnO) nanoparticles and ste... more The present investigation is directed towards synthesis of zinc oxide (ZnO) nanoparticles and steady blending with soybean biodiesel (SBME25) to improve the fuel properties of SBME25 and enhance the overall characteristics of a variable compression ratio diesel engine. The soybean biodiesel (SBME) was prepared using the transesterification reaction. Numerous characterization tests were carried out to ascertain the shape and size of zinc oxide nanoparticles. The synthesized asymmetric ZnO nanoparticles were dispersed in SBME25 at three dosage levels (25, 50, and 75 ppm) with sodium dodecyl benzene sulphonate (SDBS) surfactant using the ultrasonication process. The quantified physicochemical properties of all the fuels blends were in symmetry with the American society for testing and materials (ASTM) standards. Nanofuel blends demonstrated enhanced fuel properties compared with SBME25. The engine was operated at two different compression ratios (18.5 and 21.5) and a comparison was mad...
Applied Sciences, 2021
The first-ever use of halloysite nanotube (HNT), a relatively low-cost nanomaterial abundantly av... more The first-ever use of halloysite nanotube (HNT), a relatively low-cost nanomaterial abundantly available with minor toxicity for removing brilliant green dye from aqueous media, is reported. The factors affecting adsorption were studied by assessing the adsorption capacity, kinetics, and equilibrium thermodynamic properties. All the experiments were designed at a pH level of around 7. The Redlich-Peterson isotherm model fits best amongst the nine isotherm models studied. The kinetic studies data confirmed a pseudo model of the second order. Robotic investigations propose a rate-controlling advance being overwhelmed by intraparticle dispersion. The adsorbent features were interpreted using infrared spectroscopy and electron microscopy. Process optimization was carried out using Response Surface Methodology (RSM) through a dual section Fractional Factorial Experimental Design to contemplate the impact of boundaries on the course of adsorption. The examination of fluctuation (ANOVA) wa...
Symmetry, 2020
This paper reports a numerical study on heat transfer improvement in a double backward-facing exp... more This paper reports a numerical study on heat transfer improvement in a double backward-facing expanding channel using different convectional fluids. A finite volume method with the k-ε standard model is used to investigate the effects of step, Reynolds number and type of liquid on heat transfer enhancement. Three types of conventional fluids (water, ammonia liquid and ethylene glycol) with Reynolds numbers varying from 98.5 to 512 and three cases for different step heights at a constant heat flux (q = 2000 W/m2) are examined. The top wall of the passage and the bottom wall of the upstream section are adiabatic, while the walls of both the first and second steps downstream are heated. The results show that the local Nusselt number rises with the augmentation of the Reynolds number, and the critical effects are seen in the entrance area of the first and second steps. The maximum average Nusselt number, which represents the thermal performance, can be seen clearly in case 1 for EG in c...
Nanomaterials, 2020
Nanofluids in minichannels with various configurations are applied as cooling and heating fluids.... more Nanofluids in minichannels with various configurations are applied as cooling and heating fluids. Therefore, it is essential to have an optimal design of minichannels. For this purpose, a square channel with a cylinder in the center connected to wavy fins at various concentrations of an Al2O3 nanofluid is simulated using the finite volume method (FVM). Moreover, central composite design (CCD) is used as a method of design of experiment (DOE) to study the effects of three input variables, namely the cylinder diameter, channel width, and fin radius on the convective heat transfer and pumping power. The impacts of the linear term, together with those of the square and interactive on the response variables are determined using Pareto and main effects plots by an ANOVA. The non-dominated sorting genetic algorithm-II (NSGA-II), along with the response surface methodology (RSM) is applied to achieve the optimal configuration and nanofluid concentration. The results indicate that the effect...
Symmetry, 2020
The present investigation uses a blend of Nigella sativa biodiesel, diesel, n-butanol, and graphe... more The present investigation uses a blend of Nigella sativa biodiesel, diesel, n-butanol, and graphene oxide nanoparticles to enhance the performance, combustion and symmetric characteristics and to reduce the emissions from the diesel engine of a modified common rail direct injection (CRDI). A symmetric toroidal-type combustion chamber and a six-hole solenoid fuel injector were used in the current investigation. The research aimed to study the effect of two fuel additives, n-butanol and synthesized asymmetric graphene oxide nanoparticles, in improving the fuel properties of Nigella sativa biodiesel (NSME25). The concentration of n-butanol (10%) was kept constant, and asymmetric graphene oxide nano-additive and sodium dodecyl benzene sulphonate (SDBS) surfactant were added to n-butanol and NSME25 in the form of nanofluid in varying proportions. The nanofluids were prepared using a probe sonication process to prevent nanoparticles from agglomerating in the base fluid. The process was re...
Energies, 2020
In this numerical study, a direct contact membrane distillation (DCMD) system has been modeled co... more In this numerical study, a direct contact membrane distillation (DCMD) system has been modeled considering various angles for the membrane unit and the Reynolds number range of 500 to 2000. A two-dimensional model developed based on the Navier–Stokes, energy, and species transport equations were used. The governing equations were solved using the finite volume method (FVM). The results showed that with an increase in the Reynolds number of up to 1500, the heat transfer coefficient for all membrane angles increases, except for the inclination angle of 60°. Also, an increase in the membrane angle up to 90° causes the exit influence to diminish and the heat transfer to be augmented. Such findings revealed that the membrane inclination angle of 90° (referred to as the vertical membrane) with Reynolds number 2000 could potentially have the lowest temperature difference. Likewise, within the Reynolds numbers of 1000 and 2000, by changing the inclination angle of the membrane, temperature ...
Symmetry, 2020
Mechanical strength and thermal properties may limit the usage of an electronic component in the ... more Mechanical strength and thermal properties may limit the usage of an electronic component in the high-tech industry. This paper investigated the influence of using CuO nanoparticles in a radial configuration microchannel of a disk from the mechanical and thermal points of view. In this regard, a disk under thermal and mechanical loading had been considered. The cooling setup consisted of a radial configuration microchannel with a constant fluid volume. Water was used as the base fluid and CuO particles were used as the coolant fluid. The results showed that the use of CuO nanoparticles would reduce the maximum disk temperature, the maximum thermal stress, and the maximum stress, as well as the maximum deformation on the body. The increasing number of channels would increase the maximum stress in the object as well. Another remarkable point was that increasing the nanoparticles did not necessarily lead to a more uniform heat distribution in the disk.
Processes, 2020
Waste heat recovery plays an important role in energy source management. Organic Rankine Cycle (O... more Waste heat recovery plays an important role in energy source management. Organic Rankine Cycle (ORC) can be used to recover low-temperature waste heat. In the present work a sample power plant waste heat was used to operate an ORC. First, two pure working fluids were selected based on their merits. Four possible thermodynamic models were considered in the analysis. They were defined based on where the condenser and evaporator temperatures are located. Four main thermal parameters, evaporator temperature, condenser temperature, degree of superheat and pinch point temperature difference were taken as key parameters. Levelized energy cost values and exergy efficiency were calculated as the optimization criteria. To optimize exergy and economic aspects of the system, Strength Pareto evolutionary algorithm II (SPEA II) was implemented. The Pareto frontier solutions were ordered and chose by TOPSIS. Model 3 outperformed all other models. After evaluating exergy efficiency by mixture mass ...
Energies, 2019
This work investigates the use of iron oxide (III)–therminol 66 oil-based nanosuspensions in a co... more This work investigates the use of iron oxide (III)–therminol 66 oil-based nanosuspensions in a convective heating system with potential heating applications in the buildings sector. In an experimental study, characteristics of nanofluids were measured, including heat capacity, thermal conductivity, and density. The influences of mass flow rate and concentration of nanofluid on various parameters were quantified, such as pressure loss, friction coefficient, and heat transfer rate. For a concentration of 0.3 wt.%, the heat transfer increased by 46.3% and the pressure drop increased by 37.5%. The latter is due to the higher friction and viscosity of the bulk of the nanofluid. Although the pressure drop is higher, the thermo-hydraulic efficiency still increased by 19%. As a result, iron oxide (III)–therminol 66 presented reasonable thermal performance, higher heat transfer coefficient, and a lower pressure drop value (19% better performance in comparison with water) for the air–liquid c...
Processes, 2019
In this article, a thermodynamic study was conducted on the energetic and exergy performance of a... more In this article, a thermodynamic study was conducted on the energetic and exergy performance of a new configuration of liquid chemical looping gasification (LCLG) plant integrated with a power block to assess the overall performance of the system including exergy partitioned in syngas and first law efficiency (FLE). LCLG is a relatively new concept for the production of high-quality synthetic gas from solid feedstock such as biomass. As the temperature and pressure of the looping system are high, there is thermodynamic potential to co-produce chemical products, power and heat. Hence, in the present work, three different configurations of a power cycle were thermodynamically assessed. In the first proposed power cycle, the produced syngas from the gasifier was combusted in a combustion chamber and the exhausted gases were fed into a gas turbine. In the second and third proposed power cycles, the hot air was directly fed into a gas turbine or was used to produce steam for the steam tu...
International Journal of Numerical Methods for Heat & Fluid Flow, 2019
Purpose This paper aims to study the fluid flow and heat transfer through a spiral double-pipe he... more Purpose This paper aims to study the fluid flow and heat transfer through a spiral double-pipe heat exchanger. Nowadays using spiral double-pipe heat exchangers has become popular in different industrial segments due to its complex and spiral structure, which causes an enhancement in heat transfer. Design/methodology/approach In these heat exchangers, by converting the fluid motion to the secondary motion, the heat transfer coefficient is greater than that of the straight double-pipe heat exchangers and cause increased heat transfer between fluids. Findings The present study, by using the Fluent software and nanofluid heat transfer simulation in a spiral double-tube heat exchanger, investigates the effects of operating parameters including fluid inlet velocity, volume fraction of nanoparticles, type of nanoparticles and fluid inlet temperature on heat transfer efficiency. Originality/value After presenting the results derived from the fluid numerical simulation and finding the optim...
Physica E: Low-dimensional Systems and Nanostructures, 2018
The fluid flow and heat transfer of a nanofluid is numerically examined in a two dimensional micr... more The fluid flow and heat transfer of a nanofluid is numerically examined in a two dimensional microchannel filled by a porous media. Present nanofluid consists of the functionalized multi-walled carbon nanotubes suspended in water which are enough stable through the base fluid. The homogenous mixture is in the thermal equilibrium which means provide a single phase substance. The porous media is considered as a Darcy-Forchheimer model. Moreover the slip velocity and temperature jump boundary conditions are assumed on the microchannel horizontal sides which mean the influences of permeability and porosity values on theses boundary conditions are presented for the first time at present work. To do this, the wide range of thermo physical parameters are examined as like Da ¼ 0.1 to 0.001, Re ¼ 10,100, dimensionless slip coefficient from 0.001 to 0.1 at different mass fraction of nanoparticles. It is observed that less Darcy number leads to more local Nusselt number and also applying the porous medium corresponds to higher slip velocity.
Physica A: Statistical Mechanics and its Applications, 2018
h i g h l i g h t s • Develop 24 dissimilar ANN methods together with sensitivity analysis. • Int... more h i g h l i g h t s • Develop 24 dissimilar ANN methods together with sensitivity analysis. • Introduce the suitable architectures and training algorithms. • Measure MSEs between targets and ANN for Fe-CuO/Eg-Water.
International Journal of Numerical Methods for Heat & Fluid Flow, 2018
Purpose With respect to two new subjects, i.e. nanofluids and microchannels, in heat transfer sys... more Purpose With respect to two new subjects, i.e. nanofluids and microchannels, in heat transfer systems and modern techniques used for building them, this paper aims to study on effect of using aluminum oxide nanoparticles in non-Newtonian fluid of aqueous solution of carboxy-methyl cellulose in microtube and through application of different slip coefficients to achieve various qualities on surface of microtube. Design/methodology/approach Simultaneously, the effect of presence of nanoparticles and phenomenon of slip and temperature jump has been explored in non-Newtonian nanofluid in this essay. The assumption of homogeneity of nanofluid and fixed temperature of wall in microtube has been used in modeling processes. Findings The results have been presented as diagrams of velocity, temperature and Nusselt Number and the investigations have indicated that addition of nanoparticles to the base fluid and increase in microtube slip coefficient might improve rate of heat transfer in microt...
Journal of Mathematics and Computer Science, 2014
The effect of increase diameter of coal particles on pulverized coal combustion to produce pollut... more The effect of increase diameter of coal particles on pulverized coal combustion to produce pollutants such as NO x , CO, CO 2 and C in a 2D combustion chamber have been studied in this research by finite volume method. The numerical method is a generalized finite rate formulation, known as the Magnussen model, which is based on the solution of species transport equation for reactants and product concentration. The diameter of the pulverized coal varied from 0.0001 m to 0.0004 m which enters by the rate of 0.1 kg/s from the center of furnace. Moreover, air was preheated by a high-temperature gas generator, and the preheated oxidizer temperature could achieve 1400 C. The results show that by increasing the diameter of pulverized coal, the rate of formation of pollutants as well as NO x and the temperature of the flame decreased.
International Journal of Heat and Mass Transfer, 2019
This research aims to understand the impacts of volume concentration of Fe 3 O 4 nanoparticles an... more This research aims to understand the impacts of volume concentration of Fe 3 O 4 nanoparticles and temperature on the viscosity & thermal conductivity of liquid paraffin based nanofluid. Several experiments are conducted in the Fe 3 O 4 concentration range of 0.5-3% and temperature range of 20-90°C. Oleic acid is utilized as a surfactant for the improved dispersibility and stability of nanofluids. It was found that the nanofluid behaves as a shear thinning fluid. Additionally, it was revealed that both the thermal conductivity and viscosity boost with increasing the nanoparticle concentration, whereas when the temperature increases the viscosity reduces and the thermal conductivity rises. Moreover, the Artificial Neural Network (ANN) was utilized to model the thermal conductivity and viscosity of the nanofluid using experimental data. The accuracy of the models was assessed based on four known statistical indices including root meant square (RMS), root mean square error (RMSE), mean absolute deviation (MAE), and coefficient of determination (R 2). Results showed that the proposed model of thermal conductivity could estimate outputs with RMS, RMSE, MAE & R 2 values of 0.0678, 0.0179, 0.0041 and 0.96, respectively.
Physica A: Statistical Mechanics and its Applications, 2018
h i g h l i g h t s • Develop LBM performance to simulate the heat flux of heat source. • Natural... more h i g h l i g h t s • Develop LBM performance to simulate the heat flux of heat source. • Natural convection and mixed convection of inclined driven cavity by LBM. • Modify collision operator and macroscopic velocities equations in LBM.
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Papers by Marjan Goodarzi