Utilizing a novel mobile diagnostics lab to validate the impact of vegetative wall coverings in building cooling load reduction

Building cooling loads are driven by heat gains through enclosures. This research identifies possible ways of reducing the building cooling loads through vegetative shading. Vegetative shading reduces heat gains by blocking radiation and by evaporative air cooling. Few measured data exist, so we gathered thermal data from a vegetative wall grown in front of a Mobile Diagnostics Lab (MDL), a trailer with one conditioned room with instrumentation that collects thermal data from heat flux sensors and thermistors within its walls. In spring 2020 a variety of plants were cultivated in a greenhouse and planted in front of the south façade of the MDL, which was placed in direct sunlight to collect heat flux data. The plants acted as a barrier for solar radiation and reduced the amount of thermal energy affecting the trailer surface. Data were collected through the use of 16 heat flux sensors and development of continuous infrared (IR) images indicating surface temperature with and without plant cover. The façade surface beneath the plants was 10-30 °C cooler than exposed façade areas. In further analyses, the heat-flux data were compared to IR temperature data.

Comprehensive study of boiling regimes with use of high-speed imaging and gradient heatmetry

In the study of heat transfer during boiling, optical methods and thermometry are prevailing. The possibilities of experiment are significantly expanded by new technology – gradient heatmetry, in which heterogeneous gradient heat flux sensors with time constant of nanoseconds are used. When studying of boiling of subcooled water in a large volume on the surface of the titanium sphere, preheated up to 300-500 °C, heatmetry was combined with visualization of boiling modes using a high-speed camera Evercam 1000-4-M. It is possible to obtain the distribution of heat flux per unit area along the latitudinal coordinate and to relate the local heat flux per unit area with observed boiling regimes and initial temperatures of water and the model.