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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]

Theoretical analysis of heat transfer plays a vital role in updating the quality of heat exchanger products. Experiments cost more compared to computational costs. In this direction, this work is concerned with the unsteady and incompressible fluid flow with a rod inside a square cavity. The disturbance in the flow is induced by the motion of the top and bottom walls of the cavity. The maximum fluid flow will arise, which will help in reducing the temperature of the heated wall or rod in any physical situation. A single wall is considered to be heated, which produces heat in the neighboring fluid layers. A rod is placed to reduce the motion of the heated fluid coming from the heated wall at a high-temperature. The transmission of thermal energy along with fluid flow is carried out using the energy equation and the Navier–Stokes equation of motion, respectively. These equations are transformed to dimensionless form by appropriate parametrization and solved using the finite element method for different parameters such as Rayleigh number and Prandtl number, temperature and velocity fields and are presented graphically [ABSTRACT FROM AUTHOR]

This article deals with numerical analysis of two-dimensional viscous fluid in modified square duct. A rectangular obstacle with constant temperature at walls is placed inside it. Flow duct is depicted in Figs. 1 and 2. Influence of Prandtl number and geometry on heat transfer of working fluid is studied in two cases. Computation for the present model is made in commercial package ANSYS-Fluent. Calculations are carried at two different values of Reynolds numbers i.e., Re 40 and 200 for each of the cases. Liquid water (H 2 0) and Liquid Aniline (C 6 H 5 NH 2) are taken as working fluids. Stream functions, isotherms, vorticity, velocity and pressure profiles are examined. Graphical data for C f and Nu is presented to analyze the effect of Reynolds number and Prandtl number on heat transfer. Thermal boundary layers are discussed in each of the cases. It is shown that heat transfer has high dependance on Reynolds number and Prandtl number. Geometry of the problem has noticeable effect on heat transfer. [ABSTRACT FROM AUTHOR]