Characteristics of Wind Pressures on a Cooling Tower Exposed to Stationary and Translating Tornadoes with Swirl Ratio 0.54

Shuyang Cao; Jin Wang; Jinxin Cao

doi:10.6180/jase.2016.19.3.06

Characteristics of Wind Pressures on a Cooling Tower Exposed to Stationary and Translating Tornadoes with Swirl Ratio 0.54

Shuyang Cao¹, Jin Wang^2,3 and Jinxin Cao This email address is being protected from spambots. You need JavaScript enabled to view it.⁴

¹State Key Lab of Disaster Reduction in Civil Engineering, Tongji University, Shanghai, P.R. China
²Department of Bridge Engineering, Tongji University, Shanghai, P.R. China
³Glenn Department of Civil Engineering, Clemson University, SC, USA
⁴State Key Lab of Disaster Reduction in Civil Engineering, Tongji University, Shanghai, P.R. China

Received: February 22, 2016
Accepted: July 4, 2016
Publication Date: September 1, 2016

Download Citation: ||https://doi.org/10.6180/jase.2016.19.3.06

ABSTRACT

Current wind-resistant design of wind-sensitive structures including large-scale cooling towers is generally carried out with respect to synoptic boundary-layer-type strong winds. A swirling tornado can produce significantly different wind pressures than conventional boundary-layer wind. This paper presents both stationary and translating tornado effects on a cooling tower in a tornado vortex simulator developed at Tongji University, China. Wind pressures acting on the external surface of cooling tower model were measured at a fixed swirl ratio (S = 0.54) in the present study. Different radial distances between a cooling tower and stationary tornado vortex center were considered. Translating tornadoes with three different translation speeds (u = 0.04 m/s, 0.12 m/s and 0.2 m/s) were simulated. The results show that a tornado vortex can produce high negative wind pressures on a cooling tower surface due to the negative pressure drop accompanying a tornado. A cooling tower exposed to a tornado experiences combined effects of pressure drop accompanying a tornado and aerodynamic flow-structure interaction.

Keywords: Tornado Vortex, Cooling Tower, Wind Pressure, Aerodynamics

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