07.2020.100.108

Numerical Investigation of Turbulent Air Flow Convective Heat Transfer through a Trapezoidal Duct

Author(s):
Salah Sabeeh Abed AlKareem, Ahmed Fakhrey Khudheyer, Faiz F. Mustafa

Affiliation(s):

Automated Manufacturing Engineering Depart., College of Engineering, University of Baghdad/Al–Khwarizmi.

 Mechanical Engineering Department, College of Engineering, University of Al-Nahrain, Baghdad- Iraq.

Corresponding Author Email: dr.salah1961@coagri.uobaghdad.edu.iq ; Drahmed955@eng.nahrainuniv.edu.iq ; dr.faiz@kecbu.uobaghdad.edu.iq

This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Airflow through a circular and noncircular duct has several applications in life such as the air-conditioning system, electronic devices, and food industrials. The efficiency depends greatly upon channel’s cross-section and liquid media. This study has performed to investigate the effect of the geometrical duct and boundary conditions for turbulent airflow and heat transfer characteristics. Several cases have investigated to discover the impact of the heating side on the Nusselt number and friction factor, by utilizing the construction of computer engineering mathematical models and taking into account the analysis of the results of different forms of heating lower, upper, and both sides. The properties of heat transfer have analyzed for the conditions of turbulent flow using ANSYS Fluent2019R1 in which the turbulence model of trapezoidal-shaped with a constant thermal discharge (8000 W / m²) and airflow velocity of 2.5 m / sec have investigated. An enhancement of heat transfer characteristics have clarified in which three cases were tested and compared for Reynolds number of 4200. Results showed the average Nusselt number and friction factor significantly affected by the Reynolds number and the shape of the duct if compared with other studies mentioned in the previous works