Dynamic evaluation of the solar chimney
Date
2005-12
Authors
Rousseau, Jean-Pierre
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch : University of Stellenbosch
Abstract
Previous studies on the solar chimney have shown that its structural integrity might be
compromised by the occurrence of resonance. A structure may displace excessively when a load of
the same frequency as a structural eigen-frequency is applied. The wind gust spectrum peaks near
the solar chimney’s fundamental resonance frequency. This phenomenon poses a reliability threat,
not only to the solar chimney, but also to all high-rise, slender structures.
Structural dynamics describe the response of a structure to a varying load. The dynamic equation
incorporates four terms that bind the factors responsible for resonance: kinetic energy, dissipated
energy (damping), stiffness energy and input energy (loading). After a brief literature study on
classical chimney design procedures, the study scrutinises each of these terms individually in the
context of the solar chimney as designed to date.
A dynamic analysis is undertaken with all the above-mentioned parameters as defined and
estimated by the study. The results from the analysis show amplifications of approximately three
times the static displacements. In load cases where the wind direction inverts along the height,
higher eigen-modes are excited. However, the most severe dynamic amplification occurs at the
fundamental eigen-mode. In the context of solar chimney research, this study brings valuable new
insights regarding the dynamic behaviour of the chimney structure to the fore.
Description
Thesis (MEng (Civil Engineering))--University of Stellenbosch, 2005.
Keywords
Theses -- Civil engineering, Dissertations -- Civil engineering