Real-Time Building Air Leakage Visualizer

Lead Performer: New Mexico Institute of Mining and Technology – Socorro, NM
Partners:
-- Oak Ridge National Laboratory – Oak Ridge, TN
-- Joulea – Atlanta, GA
-- Air Barrier Association of America (ABAA) – Walpole, MA
DOE Total Funding: $1,499,911
Cost Share: $380,163
Project Term: October 1, 2023 – October 31, 2026
Funding Type: Buildings Energy Efficiency Frontiers & Innovation Technologies (BENEFIT) – 2022/23

Project Objective

The project team at New Mexico Institute of Mining and Technology (New Mexico Tech, NMIMT) and its partners will develop an Air Leakage Visualizer (ALV) system to optically characterize building envelope air leakage, which contributes to unnecessary energy consumption. Identifying and quantifying air leakage sites will enable subsequent prioritized air-sealing, which will improve the energy efficiency, comfort, air quality, and moisture durability of buildings. The project will adapt the background oriented schlieren (BOS) imaging technique to visualize building air leakage in situ and in real time, with a process that is minimally invasive to the building and its occupants.

The BOS technique is a refractive imaging method that visualizes differences in refractive index of a transparent fluid via the distortion of a background pattern. In air, this technique allows the direct visualization of plumes with an air density or temperature different from the ambient. The natural difference in the internal and external building air temperatures thus enables the direct BOS visualization of building infiltration and exfiltration, without requiring any fog or particulate seeding. The ALV system will be developed in portable and drone-based platforms to enable assessment of internal and external building envelopes. The ALV system development and implementation will be accomplished through: 

1. Objective 1: Integration of BOS and thermal imaging for real-time leakage detection and visualization.
2. Objective 2: Development of quantitative measurement methodologies to estimate the volumetric flow rate through leakage sites and mapped projection post processing on building surfaces.
3. Objective 3: Implementation of the ALV in a real building environment with air leakage induced by existing exhaust fans and/or the HVAC components.

Project Impact 

The ALV system will improve current state-of-the-art by decreasing the time and training needed to sample a building, reducing the cost and effort of performing a leak detection test and processing the data, and mitigate its impact to the building and its occupants. The developed sampling methodologies, image processing algorithms, data capture integration, and three-dimensional mapping of data to structure locations collectively will lead to increased implementation of air leakage detection and subsequent air-sealing efforts. This can help significantly reduce building energy consumption and provide natural opportunities for the technology’s commercialization.

Contacts

DOE Technology Manager: Sven Mumme
Lead Performer: Dr. Michael Hargather, New Mexico Institute of Mining and Technology