Unsteady natural convection in open ended vertical concentric annuli
General Material Designation
[Thesis]
First Statement of Responsibility
M. A. Al-Attas
.PUBLICATION, DISTRIBUTION, ETC
Name of Publisher, Distributor, etc.
King Fahd University of Petroleum and Minerals (Saudi Arabia)
Date of Publication, Distribution, etc.
1992
PHYSICAL DESCRIPTION
Specific Material Designation and Extent of Item
175
DISSERTATION (THESIS) NOTE
Dissertation or thesis details and type of degree
M.S.
Body granting the degree
King Fahd University of Petroleum and Minerals (Saudi Arabia)
Text preceding or following the note
1992
SUMMARY OR ABSTRACT
Text of Note
The problem of transient laminar free convection in the developing region of a vertical concentric annulus is investigated using an iterative implicit finite difference scheme. The following two cases are considered: Case (I): In which a step-temperature change occurs at the inner wall while the outer wall is kept adiabatic. Case (O): In which a step-temperature change occurs at the outer wall while the inner wall is kept adiabatic. The investigation is based on the boundary layer theory. The range of Grashaf number considered is 4 usd\le\ Gr\ \leusd 100,000 while the Prandtl number (Pr) is held constant at a value of 0.7. Results are presented for the variation of the temperature and velocity profiles with time and location. Furthermore, variations or the total heat absorbed by the fluid, the pressure distribution and the fluid flow rate with time are presented. The adequacy of the present solution is checked by comparing the time variation of the fluid flow rate with the available results for the vertical parallel plate channel as a limiting case. Moreover, the obtained results at large values of time are compared with the available steady state results. Finally, the fully developed results are compared with the available analytical solutions for the same geometry.