Application of Infrared Thermography for Pedestrian Wind Evaluation

Abstract

This paper describes a new experimental method using infrared thermography for the evaluation of wind impact at pedestrian level. The developed measurement system consists of a heated plate on which building models stand, an infrared video camera for detecting the surface temperature distributions on the heated plate, and a microcomputer for image processing and presentation. Since the heat loss from the heated plate can be related to air flow speeds by the principle of heat convection, the surface temperature pattern is used as an indicator of the wind impact at the pedestrian level. Results have been derived from thermal images around various buildings both on selected points and over entire affected areas that are quantified by the reduced temperature and the overall impact, respectively. The paper presents details of the experimental setup, operational principles, calibration results, application examples, and further thoughts on this technique. At the current stage, the infrared technique is capable of visualizing surface flow fields through color images, quantifying windy zones in terms of temperature variation, and evaluating the overall wind impact by further calculation.