Surface Mean Flow and Turbulence Structure in Tropical Cyclone Winds

Authors

Bo Yu, Florida International UniversityFollow

Document Type

Dissertation

Major/Program

Civil Engineering

First Advisor's Name

Arindam Chowdhury

First Advisor's Committee Title

Committee Chair

Second Advisor's Name

Amir Mirmiran

Second Advisor's Committee Title

Committee Member

Third Advisor's Name

Emil Simiu

Third Advisor's Committee Title

Committee Member

Fourth Advisor's Name

Fang Zhao

Fourth Advisor's Committee Title

Committee Member

Fifth Advisor's Name

Forrest Masters

Fifth Advisor's Committee Title

Committee Member

Keywords

hurricane wind, roughness length, coastal area, power spectral density, gust factor

Date of Defense

11-14-2007

Abstract

Hurricanes are one of the deadliest and costliest natural hazards affecting the Gulf coast and Atlantic coast areas of the United States. An effective way to minimize hurricane damage is to strengthen structures and buildings. The investigation of surface level hurricane wind behavior and the resultant wind loads on structures is aimed at providing structural engineers with information on hurricane wind characteristics required for the design of safe structures. Information on mean wind profiles, gust factors, turbulence intensity, integral scale, and turbulence spectra and co-spectra is essential for developing realistic models of wind pressure and wind loads on structures. The research performed for this study was motivated by the fact that considerably fewer data and validated models are available for tropical than for extratropical storms. Using the surface wind measurements collected by the Florida Coastal Monitoring Program (FCMP) during hurricane passages over coastal areas, this study presents comparisons of surface roughness length estimates obtained by using several estimation methods, and estimates of the mean wind and turbulence structure of hurricane winds over coastal areas under neutral stratification conditions. In addition, a program has been developed and tested to systematically analyze Wall of Wind (WoW) data, that will make it possible to perform analyses of baseline characteristics of flow obtained in the WoW. This program can be used in future research to compare WoW data with FCMP data, as gust and turbulence generator systems and other flow management devices will be used to create WoW flows that match as closely as possible real hurricane wind conditions. Hurricanes are defined as tropical cyclones for which the maximum 1-minute sustained surface wind speeds exceed 74 mph. FCMP data include data for tropical cyclones with lower sustained speeds. However, for the winds analyzed in this study the speeds were sufficiently high to assure that neutral stratification prevailed. This assures that the characteristics of those winds are similar to those prevailing in hurricanes. For this reason in this study the terms tropical cyclones and hurricanes are used interchangeably.

Identifier

FI08081552

Recommended Citation

Yu, Bo, "Surface Mean Flow and Turbulence Structure in Tropical Cyclone Winds" (2007). FIU Electronic Theses and Dissertations. 25.
https://digitalcommons.fiu.edu/etd/25