Numerical study of mixed convection for laminar flow inside a vented cavity

Other Title(s)

دراسة عددية بالحمل المختلط للجريان الطباقي داخل فجوة مفتوحة

Dissertant

al-Kikhany, Miqdad Yasir Abd

Thesis advisor

Abbud, Falah Asi
Muhammad, Ahmad K.

Comitee Members

Rishack, Qays A.
Munim, Ali A.
al-Musawy, Adil A.

University

University of Basrah

Faculty

Engineering College

Department

Department of Mechanical Engineering

University Country

Iraq

Degree

Master

Degree Date

2012

English Abstract

In this study the performance of mixed convection in a square, trapezoidal and triangular cavities is studied numerically.

Hydrodynamics and heat transfer characteristics in a laminar, 2-D, incompressible and steady state flow are considered.

An external air flow enters the cavity through an opening in the left vertical wall for rectangular and trapezoidal cavities, and in the inclined wall for triangular enclosure and exits from another opening in the right vertical wall.

The wall of the cavity is kept constant temperature for all cases, case (1) : heated on the bottom wall, case (2) : heated on the right vertical wall for three configurations (square, trapezoidal and triangular geometries), case (3) : heated on the bottom and the vertical walls for triangular geometry and case (4): heated on the inclined wall for triangular geometry, while the other walls are adiabatic.

The Navier-Stokes equations (momentum equations) and energy equation are solved by using Galerkin method based on the control finite element method with using two programs: Fortran power station program to compute the local Nusselt number, the distribution of local velocity of flow and temperature field with different axial position (0.25, 0.5, 0.75) and to know thickness of thermal boundary layer for case (1), and software package (Flexpde) program.

Results of streamlines, isotherms , average temperature and averaged Nusselt number of the heated wall are presented for Ri number values of 0, 1 and 10 and Re values of 50, 100 and 200 and Pr = 0.71.

Also the results are reported for case(1) in terms of aspect ratio (0.1 ≤ AR ≤ 1) and different outlet positions HO = 0 , 0.45 and 0.9, and the type of inlet port.

The obtained results showed that the heat transfer rate increases with increasing of Reynolds number, Richardson number and aspect ratio.

The heat transfer process enhances when the external flow is horizontal and not inclined.

As it is observed that the rate of heat transfer from the heated wall depends significantly on the position of the outlet port.

The results of streamlines, isotherms and average temperature are compared with available result of Rahman et al.

[25], an excellent agreement has been achieved.

Main Subjects

Mechanical Engineering

Topics

• Mathematical models

No. of Pages

136

Table of Contents

• APA
• MLA
• AMA

Language

English

Data Type

Arab Theses

Record ID

BIM-317166