Nusselt Number for Laminar Flow in Entrance Zone of a Hot Tube

Document Type : Original Article

Authors

Associate Professor, Sirjan University of Technology, Sirjan, Iran

Abstract

Solving many important industrial problems requires knowing the values ​​of the displacement heat transfer coefficient of one or more fluid streams in different equipment, systems or pipes. In this study, a numerical model has been developed to simulate compressible fluid flow at the inlet of a hot pipe with different angles to the horizon. In this area, the hydrodynamic and thermal boundary layers of the fluid flow are developing. Due to the turbulence of fluid flow due to the interaction of heat and fluid flow inside this pipe, three-dimensional turbulent model was used for this simulation. For this purpose, continuity equations, compressible Navier-Stokes, Reynolds stress model, and turbulent and compressible energy equations are solved simultaneously. Then, using a series of numerical runs through the concepts of experimental design and optimization methods, a prediction formula for the Nusselt number for these flows has been obtained. Finally, the ability of this formula has been investigated using a set of laboratory data.

Keywords


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