On air flow in the vicinity of tall buildings in downtown Houston, Texas

Abstract

This research presents the results of a study of actual and simulated air movements in the vicinity of tall buildings in downtown Houston, Texas. Three methods of analysis were used in this study. These methods were 1) actual observations, 2) wind tunnel simulation of flow patterns over a scale model, and 3) numerical simulation. Actual observations, consisting of the components of the three-dimensional wind, were taken at four downtown locations. Wind tunnel results showed flow patterns around a 12-block scale model of downtown Houston. Numerical simulation gave pressure and buoyancy patterns as well as the three-dimensional wind components within the model. An air pollution tracer was used to show the diffusion properties of the model as well as stagnation and ventilation areas associated with the tracer. The results showed individual stationary and transient eddies that occurred around the buildings both in the wind tunnel results and in the numerical results. Turbulent spectra were computed for actual conditions and for the numerical model. It was found that spectra from the mathematical model decline faster at higher frequencies than the theoretical and observed spectra. A composite model was constructed from the three methods of analysis showing stationary and transient eddies that occurred around the buildings.