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Partial differential equations may explain anything from planetary movement to tectonic plate, yet it is notoriously difficult to resolve them. Turbulence is present in nearly all fluid flows, and pure laminar flow is extremely unusual in practice. The Large Eddy Simulation (LES) computational model is employed for the simulation of turbulence flow on a spillway having four inlets with a single outlet. Such flows are observed at hydroelectric power dams all over the world. The fluctuated flows produced a large amount of energy in terms of electricity that costs a very low amount compared to the energy obtained in tidal power sectors. In the production of hydropower energy, the flow simulation is of great interest. This paper focuses on the study of turbulence kinetic energy with the help of a LES model. The spillway considered in this paper contains four inlets and a single outlet. The four inlets will allow more flow which will insert more pressure nearer the outlet. The kinetic energy is computed at the inlets and outlet in the turbulent flow. The fluctuated velocity along with the mean velocity at the inlets and outlet is also computed along with the pressure. The C++-based programming is made, which is simulated in Open-source Field Operation and Manipulation (OpenFOAM). The graphs are presented for a better understanding of readers. [ABSTRACT FROM AUTHOR]

A heat exchanger is a device that transmits heat energy from one object to another, or within the same object. Examples of heat exchanger include a boiler, an oven and a cooker. Experimental techniques for testing these devices make it more costly and time-consuming. Consequently, computational fluid dynamics (CFD) can manage heat exchanger systems and their performance with ease. The actual impacts of what is being examined may then be predicted computationally which yields a precise output with approximate results. The designed geometry includes a rectangular duct with an inlet, outlet and two obstacles of equal height. The Navier–Stokes equations for the fluid flow are used. During the meshing process, the continuous geometric space of an item is divided into thousands or more forms, which helps to correctly identify the object's physical shape. The desired model is computed numerically. Finite volume method (FVM) is used to study the results at a low Reynolds number (around 2. 3 × 1 0 6). The goal is to theoretically analyze the transmission of heat and fluid resistance to the flow. The CFD findings with experimental data are compared to confirm the model predictions. A CFD model based on the FVM and experimental data from a flow cell is used to study how fluid moves through ducts. This study focuses on the pressure, velocity and temperature fields of a fluid moving through a rectangular duct. As the top wall fluid temperature rises, the temperature distribution changes. Increasing fluid flow declines the temperature distribution. Temperature distribution grows with duct heat flow. As the flow rate rises, so does dispersion. Furthermore, as flow rate and velocity distribution drop, pressure distribution rises. [ABSTRACT FROM AUTHOR]

Practically speaking, fluid flow in round and noncircular nozzle is a very regular occurrence. The cold and hot water used in our homes is delivered to us via pipes. Water is delivered throughout the city via large pipe networks. Large pipelines carry natural gas and oil hundreds of kilometres from one place to another. During the operation of an engine, cooling water is carried by hoses to the radiator's pipes, in which it is cooled as it travels. Experimentally, we detected the results of the model because there is no restriction on the application of experimental research to a certain sector or kind of concept. It may be used for a broad range of events and circumstances. Under parabolic velocity conditions, fluid (Water Pr 6.9) flows from the inlet position. The top and bottom walls of the rectangular nozzle are also moving at the same velocity as they are at the inlet position. Due to the movement of the walls, fluid is compressed in the particular region and also exhibits the same parabolic behavior. The solution of the coupled equations is determined by using the Finite Volume Method (FVM). When partial differential equations are expressed as algebraic equations, the FVM may be used to evaluate them. It can be used to evaluate elliptic, parabolic, and hyperbolic partial differential equations. Using FVM, it is necessary to know the values (and derivatives) of multiple variables at the cell faces, when the values (and derivatives) of these variables are only known at the cell centres. When determining these variables for convective terms, it is common to take the direction of the flow into consideration. The numerical results of the velocity and the pressure could be seen in the rectangular nozzle. [ABSTRACT FROM AUTHOR]

According to new research, methane emissions contribute 25 percent more to global warming than previously assumed. Methane is a crucial precursor gas of tropospheric ozone, a dangerous air pollutant. Methane emissions are responsible for almost half of the reported growth in tropospheric ozone levels on a global scale. But it plays a vital role as an energy source, therefore, the study of methane cut reservoirs is essential. The injection of air can extract additional energy in high methane-cut reservoirs. The analysis is made to compute the theoretical potential of low air flooding in high methane-cut reservoirs. Computational Fluid Dynamics (CFD) is used to study the impact of injecting air on methane. The presence of carbon dioxide and oxygen when injected into the methane cut reservoir produces high-pressure air injection that may cause significant safety damage such as the potential for corrosion or explosion. Past field studies and reported solutions indicate that there are no insurmountable problems in the execution of high-pressure air injection. The results are harmful and need to take useful safety precautions for the engineers who are interested in experiments. The users of CFD use mathematical laws and models that exactly represent the phenomenon they are dealing with. The pressure induced by the air injection is simulated with the help of the Finite Volume Method (FVM). The velocity field near the outlet arises as higher pressure of air from the inlet is observed, whereas, the pressure near the outlet declines. The findings of this study can help for better understanding of outflow of methane from methane reservoirs. [ABSTRACT FROM AUTHOR]

In computational fluid dynamics (CFD), the mathematical description of a physical phenomenon that involves fluid flow, combustion, and chemical reaction is combined with a numerical solution of the problem via the use of a computer process. Computational fluid dynamics has emerged as a critical tool for comprehending and forecasting the behavior of reacting flows, which are fundamentally complicated systems involving the intricate interplay of chemical kinetics and fluid mechanics. Among the numerous open source CFD packages, the widely used C++ finite volume simulation toolbox OpenFOAM (Open-Source Field Operation and Manipulation) has a number of advantages, including an object-oriented framework, the ease with which multiphysics modules can be added, and its free availability. However, numerous shortcomings have been identified regarding its application to chemically reacting flows, most notably incomplete splitting schemes, inadequate ordinary differential equation (ODE) solvers for stiff chemistry, and oversimplified mixture transients. This article focuses on the combustion flow in an intake manifold. A sample intake manifold consists of two inlets and one outlet. The finite volume method is used for computing the mathematical modeling developed for combustion. The focus of the attention will be the demonstration of the structure of the flame. The energy deposition and pressure near the outlet are higher. The results are compared and found a good agreement between OpenFOAM and DUNE (Distributed and Unified Numerics Environment) numerics. [ABSTRACT FROM AUTHOR]

The article focuses on the mixed convective flow of Ag–ethylene glycol nanofluid. The analysis is carried out for a cavity having center as heated. The relatively moving side walls of cavity are retained at low constant temperature while constant heat source is examined in the bottom wall. The rest of the bottom and top walls remain insulated. Cattaneo–Christov heat flux is implemented in the analysis of heat transfer. Heat transfer rate is dig out for the case of Fourier's heat flux, as for the case of Cattaneo–Christov heat flux it gives implicit expression, which is difficult to analyze and simplify. The problem is analyzed numerically via projection method. Higher heat transfer is observed for the Fourier's law as compare to Cattaneo–Christov heat flux. The results are expressed by isotherms, streamlines, velocity field, and average Nusselt numbers. • Nanoparticles in a viscous flow is studied. • The impact of thermal relaxation time is considered. • Comparison of Fourier's and Cattaneo–Christov heat flux is presented. • Thermal relaxation declines the transfer of heat. [ABSTRACT FROM AUTHOR]