MSc Thesis Examination - Jacob Lachapelle

Jacob Lachapelle will defend his MSc thesis "A microscale 3‐D model of urban outdoor thermal exposure (TUF‐Pedestrian): impacts of street tree configuration" 

Advisor: Dr. Scott Krayenhoff

Advisory Committee: Dr. Jon Warland, Dr. Ariane Middel

Everyone is welcome.

If you would like to attend, please inquire with our Graduate Program Assistant (ses.gradsec@uoguelph.ca)
 

Abstract

Street trees create shade and provide effective cooling to urban pedestrians during hot weather. However, existing simulation tools may not be sufficient to inform optimization of street tree placement for this purpose. A microscale three‐dimensional (3‐D) urban radiation and energy balance model, TUF‐Pedestrian, is developed to simulate pedestrian radiant exposure and study urban tree placement. TUF‐Pedestrian explicitly simulates the shortwave and longwave radiative impacts of trees on their surroundings. It also includes a pedestrian that absorbs radiation, permitting calculation of a summary metric of radiant exposure: the mean radiant temperature (TMRT). Model evaluation demonstrates that TUF‐Pedestrian accurately simulates incoming directional shortwave and longwave radiation fluxes on pedestrians and associated TMRT in urban environments with and without tree cover. Subsequently, the model is applied to understand the variation of pedestrian TMRT as a function of different street tree configurations in hot weather. Results suggest it is important to consider street orientation and latitude (solar angle) in terms of the placement of street trees relative to pedestrian walkways. Importantly, additional radiant cooling of pedestrians during hot afternoons per unit addition of tree cover decreases modestly as existing tree cover increases. Optimizing street tree configuration in urban canyons for pedestrian thermal comfort is a complex task that can be supported with simulation tools such as TUF‐Pedestrian.