Employing a new micro-spray model and (MWCNTs - SWCNTs) - H2O nanofluid on Si-IGBT power module for energy storage: A numerical simulation

CFD analysis of Al2O3-syltherm oil Nanofluid on parabolic trough solar collector with a new flange-shaped turbulator model

The effect of MoS2–Ag/ H2O hybrid nanofluid on improving the performance of a solar collector by placing wavy strips in the absorber tube

Increasing heat transfer in flat plate solar collectors using various forms of turbulence-inducing elements and CNTs-CuO hybrid nanofluids

Recent studies in the field of thermal engineering revealed that employing nanofluid as a working fluid in a specific channel, considering both turbulators and magnetic field effect is scarce. Studies on the convective heat transfer performance of the thermal systems focus mostly on the effect of using either nanofluid as a new fluid, magnetic field, or turbulators. This review highlights the single and combined effects of these parameters on the heat transfer enhancement of such systems. Nanofluid type, its volume fraction, channel and turbulator geometry, magnetic field type, and flow regime were considered as the base parameters while the enhancement in heat transfer is evaluated. From a state-of-the-art review, it was noticed that most studies reveal that increasing the volume fraction of nanofluid, magnetic field strength, and Reynolds number can attain an upsurge in the heat transfer in a specific channel. Nevertheless, drawbacks are poorly discussed in the open literature. Regarding the turbulator geometry, which actually limits the magnetohydrodynamic and thermal boundary layer development, its complexity boosts also the convective heat transfer. The maximum heat transfer enhancement was noticed for higher nanoparticle volume fractions, higher magnetic field strengths, and complex geometries in channel flow. The highest heat transfer improvement was obtained for the MWCNT/H2O nanofluid (i.e., between 70% and 190%). With the effect of magnetic field intensity of Ha = 30 applied to the Cu/H2O nanofluid flow, a thermal recovery of 76% was achieved. Concluding, this comprehensive review can be beneficial to researchers working in the field of flow and heat transfer applications with the use of nanofluid, turbulator, and magnetic field together. 

Effects of using nanofluid, applying a magnetic field, and placing turbulators in channels on the convective heat transfer: A comprehensive review

Geothermal energy is among the types of renewable energies, which has variety of applications nowadays. The main purpose of this research is to design better geometry of heat exchange pipes to be placed into the construction foundation pile that can maximally use the clean energy hidden in the depths of the ground through these pipes and increase the strength and longevity of foundation piles, in terms of structural. Therefore, five heat foundation piles connected in series were exploited for four different geometries. The simulation was performed by ANSYS- FLUENT commercial software, which has high computational accuracy with validation made. The results indicate that the U6 heat exchanger at the depth of 25 m has the maximum efficiency and thermal performance capacity, illustrating the fact that its heat transfer rate is the highest compared to other geometries and then spiral, W, and U geometries have maximum efficiency respectively. Moreover, by increasing the contact area of the pipes and the concrete, the heat transfer rate will increase, and the temperature of the output fluid will be gradually reduced.

Evaluating and optimizing the geometry of thermal foundation pipes for the utilization of the geothermal energy: Numerical simulation

In this research, the transient state of a solar power plant with a parabolic receiver in several parts of Iran (6 cities) with the effect of adding a latent heat storage system is investigated. For this purpose, first, the performance of the solar power plant will be evaluated by TRNSYS simulation software and then a latent heat storage system will be added to it. Accordingly, the three types of phase change materials (PCMs) including H250, NaNO3 and KNO3 were investigated. The results show that the performance of the latent heat storage system is highly dependent on the type of phase change material (PCM) and its type should be selected according to the power plant conditions. The addition of a solar heat storage system reduced the amount of heat required in the boiler overnight at the plant. The latent heat storage system performed best by selecting NaNO3 as the phase change agent (PCM). In addition, the effect of different climates studied in six cities of Mashhad, Tabriz, Shiraz, Kerman, Zahedan and Tehran shows that Zahedan has a more suitable location than other cities and solar fraction and power plant efficiency are higher in this city. The annual solar fraction in this power plant was about 68.9%. Further, it was determined that by using the north-south tracking system, more energy can be absorbed in the collectors and using this system will reduce the angle of impact on the collector. 

Behzad Shaker

Papers

CFD analysis of Al2O3-syltherm oil Nanofluid on parabolic trough solar collector with a new flange-shaped turbulator model

Evaluating and optimizing the geometry of thermal foundation pipes for the utilization of the geothermal energy: Numerical simulation

Simulation of a solar power plant with parabolic receivers in several parts of Iran in the presence of latent heat thermal energy storage system