Researchers at the Department of Energy’s Oak Ridge National Laboratory (ORNL) have a created a new detection system that allow home energy auditors to see air leaking from a building in real time with the help of a camera.
Leaky buildings can mean higher energy bills by using more energy to heat/cool homes. The air that is being controlled escapes from a home through windows, doors and walls. Knowing and then fixing where these areas are can be a long task that can be expensive.
Blower door testing is the traditional way to detect leaks, in association with smoke. It’s used in conjunction with the blower door to see where the smoke is exiting. Other detection techniques have been used throughout recent years including pulsed lasers, acoustics and ultrasound technology.
ORNL’s air leakage detection system is based on background-oriented schlieren photography, a process used to capture fluid flow. The technology dates back to the 1860s, schlieren photography has most recently and more widely been used to photograph the flow of air around aeronautical objects.
According to the lead ORNL researcher Philip Boudreaux, the technique uses small shifts in the background of a sequence of images to visualise leaking air that has a different temperature than the surrounding air. The temperature difference creates what Boudreaux refers to as a mirage when viewed in front of a building’s façade.
“The mirage is too small to be seen with the naked eye, but by camera it looks like wavy patterns that you might see rising up from the pavement on a hot day”
To find out more go to https://www.ornl.gov/news/air-leak-detection-system-visualizes-building-drafts-click-camera
