In this work, the flow conditions within the University of the District of Columbia (UDC) urban campus are predicted from wind-induced noise. Wind-induced noise obtained from a collection of spatial distributed microphones are used to estimate the mean velocity airflow and wind noise distribution across the UDC campus. Wind speed and direction are estimated by fitting the second-order statistics of semi-empirical models of wind noise distribution from microphone measurements to analytical models in the least squares sense. The accuracy of the proposed is investigated for average microphone separation and time resolution. Comparisons of the wind speed and direction results to ultrasonic anemometer measurements are discussed.

In this work, reconstruction techniques for the spatial interpolation and extrapolation of sound fields in urban environments are presented. Gaussian processes are generally used for sound field reconstruction from limitedly observations of isotropic acoustic fields. However, this model is often not applicable for the anisotropic urban environments including urban street canyons and enclosed spaces, when the complexity of the sound field is high in the mid-frequency regime, unless diffusely reflecting boundaries are assumed. Two different techniques are compared for reconstructing the sound field: the least-squared method and the Kirchhoff-Helmholtz integral equation method. Of particular interest is the reconstruction of the sound field with a minimal number of irregularly and arbitrarily distributed microphone measurements. Therefore, the techniques will not require knowledge of the microphone positions. A successive series approximation approach is presented to enhance the microscale prediction of the Kirchhoff-Helmholtz integral equation method. The sound field reconstruction results from limited urban environment observations for both methods are presented and discussed.

In this work, generated vortices within an urban microspaces are investigated numerically and experimentally. Of particular interest are vortices within an urban street canyon. Computational fluid dynamics simulations of wind vortices are compared to experimental observation of similar urban street geometries within the District of Columbia. Additionally, the vortex and ground interaction are investigated for acoustic propagation. Preliminary results are presented and discussed.

This work aims to study microclimate changes within urban microspaces using atmospheric acoustic tomography (AAT). Of particular interest are the imaging of wind velocity and temperature field variations. To reduce the inaccuracy of using the conventional AAT straight ray model, a nonlinear reconstruction algorithm is employed. Simulated and measurement results are presented and discussed.

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