The present study aims to enhance the hydrothermal performance of a porous sinusoidal double-layered heat sink using nanofluid. The optimum thickness of metal foam (nickel) for different Reynolds numbers ranging from 10 to 100 for the laminar regime and Darcy numbers ranging from 10−4 to 10−2 is obtained. At the optimum porous thicknesses, nanofluid (silver–water) with three volume fractions of nanoparticles equal to 2, 3, and 4% is employed to enhance the heat sink thermal performance. Darcy–Brinkman–Forchheimer model and the local thermal non-equilibrium model or two equations method are employed to model the momentum equation and energy equations in the porous region, respectively. It was found that in the cases of Darcy numbers 10−4, 10−3, and 10−2 the dimensionless optimum porous thicknesses are 0.8, 0.8, and 0.2, respectively. It was also obtained that the maximum PEC number is 2.12 and it corresponds to the case with Darcy number 10−2, Reynolds number 40, and volume fraction of nanoparticles 0.04. The validity of local thermal equilibrium (LTE) assumption was investigated, and it was found that increasing the Darcy number which results in an enhancement in porous particle diameter leads to some errors in results, under LTE condition.

Heat and fluid flow analysis of metal foam embedded in a double-layered sinusoidal heat sink under local thermal non-equilibrium condition using nanofluid

Coupling a Hydronic Heating Pavement to a Horizontal Ground Heat Exchanger for harvesting solar energy and heating road surfaces

Empirical and numerical assessments on corrugated and twisted channels as two enhanced geometries

A parametric analysis is performed on Al2O3–water nanofluid flow through the heated corrugated channels. The mixture approach is adopted to model the Al2O3–water nanofluid flow, and the finite volume method is applied for the discretization of governing equations. The numerical procedure is validated for the straight channel by using the available correlations. The studied parameters are the wave shape (triangular, trapezoidal, and sinusoidal), phase shift (0, π/2, and π), nanoparticle concentration (0–4%), and Reynolds number (6000–22,000). It is found that the trapezoidal configuration proposes the highest values of Nusselt number, while the sinusoidal one offers the best overall hydrothermal performance. Also, the results show that the channel with lower phase shift presents a better hydrothermal performance. The heat transfer rate and performance index enhance with the increase in Al2O3 nanoparticle volume fraction. Further, new correlations are presented for the subsided cases.

Investigation of corrugated channel performance with different wave shapes

Effective parameters on the performance of ground heat exchangers: A review of latest advances

By the increase of population and development of technology in recent years, energy demand has also increased. Due to the limitedness of energy resources, new research works and inventions are needed to ensure the continuity and efficient consumption of these sources and addressing economic problems. It is important to provide low-cost energy in living, industrial and commercial spaces with zero emission. Solar energy is an unlimited, clean and abundant energy source. However, the conditions of taking full advantage of sun vary seasonally. With the storage and conversion of solar energy, the sun, which is abundant in the summer period, can be used in the winter period. In this case, energy storage and conversion performance is extremely important to obtain the highest rate and efficiency from solar energy. The application and development of nanomaterials are popular issues in all fields, especially in energy storage and conversion applications, and play key roles in storage efficiency. Furthermore, phase change materials (PCMs) have successful and potential applications in the storage and conversion of solar thermal energy. In this study, research on efficient nanomaterials used in solar energy storage and conversion has been reviewed and discussed. According to the reviewed studies, efficiency was increased with the use of nanomaterials in solar energy storage and conversion systems. Particular attention was paid to the high charge and discharge rates of graphene and graphite-containing nanomaterials, as well as nanoparticles and composite materials added to PCMs. In addition, it has been stated that thermal energy is stored efficiently by the application of PEG support to composite materials. According to previous studies, the size, concentration, shape, and phase change of materials had critical effects on the storage efficiency of composite materials. • We reviewed the storage performance of efficient nanomaterials for STES systems. • Studies in sensible, latent and thermochemical methods for STES systems are summarized in detail. • Graphene and graphite-based nanomaterials were found to increase charge/discharge rates. • Nanocomposite materials have been found to provide efficiency in long-term storage. • Solar energy systems with nanoparticles added to base salts have promising performance. 

Samaneh Arman

Papers

A novel review on the efficiency of nanomaterials for solar energy storage systems

Effects of the geometric parameters on the thermal-hydraulic performance of the wavy tubes

State-of-the-Art Review of Machine Learning Applications in Additive Manufacturing; from Design to Manufacturing and Property Control

A new idea for improving the horizontal straight ground source heat exchangers performance

Prediction of elastic properties of thermoplastic composites with natural fibers