Mehdi Hosseini Abadshapoori

Bio: Mehdi Hosseini Abadshapoori is an academic researcher from Sharif University of Technology. The author has contributed to research in topics: Lattice Boltzmann methods & Nanofluid. The author has an hindex of 2, co-authored 4 publications receiving 9 citations.

3D investigation of natural convection of nanofluids in a curved boundary enclosure applying lattice Boltzmann method

Abstract: Purpose The purpose of this paper is to investigate the natural convection behavior of nanofluids in an enclosure. The enclosure is a 3D capsule with curved boundaries filled with TiO2-water nanofluid. Design/methodology/approach In this paper, a multiple relaxation times lattice Boltzmann method (MRT-LBM) has been used. Two-component LBM has been conducted to consider the interaction forces between nanoparticles and the base fluid. Findings Results show that the enhanced Nusselt number (Nu*) increases with the increase in volume fraction of nanoparticles (ϕ) and Ra number and decrease of nanoparticle size (λ). Additionally, the findings indicate that increasing volume fraction beyond a certain value decreases Nu*. Originality/value This paper presents a MRT model of lattice Boltzmann in a 3D curved enclosure. A correlation is also presented based on the current results for Nu* depending on Ra number, volume fraction and size of nanoparticles. Furthermore, a comparison for the convergence rate and accuracy of this model and the SIMPLE algorithm is presented.

Numerical simulation of MHD mixed convection flow of Al2O3–water nanofluid over two hot obstacles

Abstract: The problem of cooling two hot blocks in a novel geometry using magnetohydrodynamic flow of Al2O3–water nanofluid has been studied utilizing a D2Q9 Lattice Boltzmann Model. While the Hartmann number (Ha) takes 0, 50, or 100 values, the Richardson number (Ri) varies between 0.02 and 20. Four variations of the geometry are selected. The gravity angle is set to be either 0∘ , 30∘ , or −30∘ . Results reveal that the Nusselt number (Nu) increases as Ri increases for all cases. Furthermore, the Hartmann number has a deteriorating effect on the Nusselt number except for low Ri numbers. In addition, the results indicate that while the geometrical configuration is having a considerable impact on the average Nusselt number at low and high Richardson numbers, it has a negligible effect at the mixed convection flow. The best angle for the gravitational force is also between 0 and −30∘ . A new correlation for the Nu number based on all parameters is also presented.

Effect of nanofluids on heat transfer and cooling system of the photovoltaic/thermal performance

Abstract: Purpose Effective cooling is one of the challenges for photovoltaic thermal (PVT) systems to maintain the PV operating temperature. One of the best ways to enhance rate of heat transfer of the PVT system is using advanced working fluids such as nanofluids. The purpose of this research is to develop a numerical model for designing different form of thermal collector systems with different materials. It is concluded that PVT system operated by nanofluid is more effective than water-based PVT system. Design/methodology/approach In this research, a three-dimensional numerical model of PVT with new baffle-based thermal collector system has been developed and solved using finite element method-based COMSOL Multyphysics software. Water-based different nanofluids (Ag, Cu, Al, etc.), various solid volume fractions up to 3 per cent and variation of inlet temperature (20-40°C) have been applied to obtain high thermal efficiency of this system. Findings The numerical results show that increasing solid volume fraction increases the thermal performance of PVT system operated by nanofluids, and optimum solid concentration is 2 per cent. The thermal efficiency is enhanced approximately by 7.49, 7.08 and 4.97 per cent for PVT system operated by water/Ag, water/Cu and water/Al nanofluids, respectively, compared to water. The extracted thermal energy from the PVT system decreases by 53.13, 52.69, 42.37 and 38.99 W for water, water/Al, water/Cu and water/Ag nanofluids, respectively, due to each 1°C increase in inlet temperature. The heat transfer rate from heat exchanger to cooling fluid enhances by about 18.43, 27.45 and 31.37 per cent for the PVT system operated by water/Al, water/Cu, water/Ag, respectively, compared to water. Originality/value This study is original and is not being considered for publication elsewhere. This is also not currently under review with any other journal.

Three-dimensional analysis on natural convection inside a T-shaped cavity with water-based CNT–aluminum oxide hybrid nanofluid

Abstract: Three-dimensional numerical simulation on natural convection inside the T-shaped cavity, filled with water-based hybrid nanofluid of CNT–aluminum oxide is performed by vorticity–vector potential formalism. The variables considered are size of enclosure (0.1 < L < 0.9), volumetric percentage of nanoparticles (0 < φ < 4%), fraction of CNT composites (0 < fr < 1), and Rayleigh number (103 < Ra < 106). The heat transfer is increased with the increase in size, volumetric percentage of nanoparticles, fraction of CNT composites, and Rayleigh number.

The effect of air injection system on airlift pump performance

Abstract: In the current study, a novel design of an air injection system for an airlift pump was designed and tested. The pump has a circular cross-section and composed of three parts; suction pipe, injection system, and riser pipe. The riser pipe has a diameter of 31.7 mm and a length of 2 m. The performance of the pump was tested using different submergence ratios, ranging from 0.15 to 0.3, and the injected airflow rate was ranging from 1.65 kg/h to 13.32 kg/h. The results showed that both the airflow rate and the submergence ratio have a significant effect on the capacity and performance of the pump. Besides, it was found that the best range of pump efficiency was in the slug and slug-churn flow regimes. Moreover, the highest efficiency was at the most significant submergence ratio of 0.3. A reasonable enhancement in water flow rate was achieved using the current air injection design when compared with the conventional airlift pump injections system.