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In this study, the impact of Newtonian heating is incorporated into a two-dimensional ferrofluid. The flowing chemically reactive species of ferromagnetic fluid fluids. By virtue of this property, such fluids are necessary for heat transfer in engineering equipment and devices. The main focus of flowing fluids in these devices is to enhance the transfer of heat and decrease friction drag at the surface. Thus, the paper focuses on the analysis of the rate of heat transfer via Fourier's law. The fluid in the problem is taken to be a viscous fluid containing chemically reactive species. Chemically reactive species consist of two or more base fluids. Therefore, the main interest is in watching the heat transfer impacts on the ferromagnetic fluid. This is important in the presence of chemically reactive species. The results obtained are shown to be in excellent agreement in specific cases available in literature. [ABSTRACT FROM AUTHOR]

The pursuit of superior working fluids for heat and mass transfer systems in the industry is on the rise, inspired by not only to maximize revenue but also to accommodate heat dissipation or chemical separation under extreme conditions. The addition of a small amount of nanoparticle, a product called nanofluid, has been initiated over the last decade. In particular, researchers have employed carbon nanotubes (CNTs) into conventional fluids as their preferred nanoparticles due to the merits of having a remarkable thermal conductivity compared to other nanoparticles. Here, we present a comprehensive and up to date review of this incredible fluid being applied in various heat transfer (convective and boiling) and mass transfer systems such as heat exchangers and separators. Other critical parameters associated with the practicality of the CNT nanofluids such as pumping power and efficiency are also discussed. We surveyed a remarkable range of results of some of the heat and mass transfer studies that strongly depend on the inherent CNT nanofluid characteristics and operating conditions such as CNT treatment, size, concentration, Reynolds number, and so on. A major conclusion that can be drawn from this review is the significantly higher heat transfer coefficient at lower pressure drop or pumping power of the CNT nanofluid compared to other nanofluids, which implied better thermal performance of the heat transfer system. Besides that, the concentration of CNT is the influential factor to achieve optimum boiling heat transfer while the mass transfer performance of the CNT nanofluid is moderately good against other nanofluids. Additionally, CNT treatment using covalent functionalization is crucial for the overall stability and performance of the CNT nanofluid. However, several issues that inhibit their widespread use such as possible corrosion-erosion in systems, lack of risk assessments, and high cost of CNT nanofluid must be thoroughly addressed in future studies. [ABSTRACT FROM AUTHOR]

Active and passive cooling are the two possible methods for removing heat. An active cooling system is the one that involves the use of energy as opposed to passive cooling that uses no energy. Passive cooling methods are cost effective and more reliable than active cooling due to the absence of moving parts. Microchannel heat sink is one of high-tech devices that have widely considered passive cooling methods especially for electronics cooling. In this paper, the use of passive cooling methods in microchannel heat sink is comprehensively discussed. This paper also present the effects of some important parameters such as the type of channel types, surface roughness, fluid additives, and Reynolds number on the rate of heat transfer in microchannel heat sink. Finally, the conclusions and important summaries were presented according to the data collected. [ABSTRACT FROM AUTHOR]

Nanofluids have gained significant attention in recent years due their great potential for heat transfer enhancement . The heat transfer of nanofluids can be numerically studied using a single-phase or two-phase approaches. The first assumes that the fluid phase and nanoparticles are in thermal equilibrium and move with the same velocity, while the second requires more computational effort but provides the possibility of understanding the behavior of both fluid phase and solid particles in the heat transfer mechanism. This paper reviews various computational approaches to predict fluid flow and heat transfer characteristics of nanofluids. The characteristics of single-phase and two-phase (volume of fluid, mixture, Eulerian–Lagrangian and Eulerian–Eulerian) approaches have been analyzed and discussed systematically. Latest development and recent researches related to the computational nanofluids are also given. [ABSTRACT FROM AUTHOR]

Nanofluid, an advanced type of fluid containing small quantity of nanoparticles (usually less than 100 nm), has been proven to provide more efficient heat transfer compared to conventional fluids. The dispersion of a small amount of solid nanoparticles in conventional fluids such as water or ethylene glycol changes their thermal conductivity remarkably. Recently, nanofluid has been used as a heat transfer fluid to enhance the performance of solar collector devices. This paper reviews recent progress and applications of nanofluids in stationary solar collectors. In addition to reviewing the efficiency of solar collectors which use nanofluids, the paper also discusses the impact of nanofluid usage in solar collector based on economic and environmental viewpoints. Finally, the challenges and future trends related to the application of nanofluids in thermal solar collector is discussed. [ABSTRACT FROM AUTHOR]

In this article, turbulent flow characteristic of nanofluids is thoroughly reviewed. Turbulent flows have unique characteristics and are preferred in many industrial applications. Therefore, this paper reviews different techniques used to enhance heat transfer using nanofluids within turbulent regime. This paper also presents the effects of some important parameters such as nanoparticle type, nanoparticles concentration, and Reynolds number on heat transfer rate. Studies on numerical techniques are also discussed. Finally, the conclusions and important summaries are presented according to the data collected. [ABSTRACT FROM AUTHOR]