CFD to VorTECH Pressure-Field Comparison and Roughness Effect on Flow
Publication: Journal of Structural Engineering
Volume 146, Issue 9
Abstract
A numerical simulator that very closely resembles the experimental tornado simulator facility called VorTECH at Texas Tech University (TTU) is modeled using three-dimensional simulation. Details of an efficient, simplified computational fluid dynamics (CFD) model without vanes are presented. The pressure field is compared with experimental observations with an emphasis on the vortex breakdown, touchdown, and post-touchdown phase of a tornado. The simulation results indicate that the time-averaged radial ground pressure profile follows a similar trend with the experiment in terms of pressure field distribution. The tornado vortex core is found to be in a transient state in both space and time. The flow at higher swirl ratios has also been observed to lead to greater unsteadiness in flow. Moreover, the effect of roughness on the critical touchdown swirl ratio was also investigated, and increasing roughness length was found to increase the critical touchdown swirl ratio and vice-versa.
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Data Availability Statement
Some or all of the data, models, or code generated or used during the study are available from the corresponding author by request:
1.
All data.
2.
Details of computational model.
Acknowledgments
The authors acknowledge the support received from the National Science Foundation under award number CMMI-1762999.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 146 • Issue 9 • September 2020
Copyright
©2020 American Society of Civil Engineers.
History
Received: Jun 10, 2019
Accepted: Apr 8, 2020
Published online: Jun 29, 2020
Published in print: Sep 1, 2020
Discussion open until: Nov 29, 2020
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