CUR - The Council on Undergraduate Research

Validating the impact of vegetative wall coverings on building cooling loads using heat-flux sensors and infrared images

Authors: Oluwatobiloba Fagbule (Architecture) and Rushi Patel (Mechanical Engineering) Faculty Mentor: Ulrike Passe, Department of Architecture, Director for Building Energy Research, Iowa State University, 146 College of Design. Ames Iowa, 50011 Funded by the Center for Building Energy Research 

Building cooling loads are driven by heat gains through enclosures. This research looks at ways of reducing the building cooling load, we look at a method through Vegetative shading. Vegetative shading reduces these gains by blocking radiation and by evaporative air cooling. Few measured data exists. We aimed at gathering thermal data from the vegetative wall and heat flux sensors through the Mobile Diagnostics Lab (MDL), a trailer that collects thermal data from heat flux sensors and thermistors inside its walls. A variety of plants were cultivated in an ISU greenhouse in spring 2020 and planted in front of the south façade of the MDL, which is placed in direct sunlight so it can collect heat flux data. The plants on the south façade act as a barrier for the solar radiation to reduce the amount of heat energy falling onto the surface of the south wall of the trailer. We collected data through the 16 heat flux sensors and continuous infrared images measuring surface temperatures. The infrared images were used to capture surface temperatures with and without plant cover. Thermal data from the pictures were tabulated showing the relation of the surface temperature with and without plant cover per month. The results were analyzed using direct comparison and sol-air temperature calculations. So far the results show the façade surface beneath the plants has a lower temperature (10°C-30°C) than the exposed façade In the MDL, heat flux and temperature data is continuously collected into the winter season using 16 sets of heat flux sensors and thermistors. The heat flux data will be compared with the IR temperature and weather data collected at Ames weather station to calibrate an energy model and prepare the heat flux data as an input for our CFD models.

Additional Abstract Information