ACOUSTIC BEAMFORMING USING PHASED MICROPHONE ARRAY: A NOVEL METHOD TO DETECT AIR INFILTRATION
MetadataShow full item record
The major issue of air in ltration in buildings is the soaring energy consumption. According to the US Department of Energy, in 2003 it was estimated that there was 48% of space conditioning energy consumption due to air in ltration. This is responsible for 9.19 quadrillion Btu (quads) of energy which costs half billion dollars annually. If, just the HVAC energy consumption due to in ltration can be taken care of; then 1.2 quads of energy can be saved i.e., around 60 million dollars per year. The present state-of-the-art technique to measure air leakage rates is the Blower Door method. In order to locate air leakage spots in buildings, Tracer Gas/ Smoke Stick technique is used. The major drawbacks of these techniques are; the blower door method requires building evacuation and becomes impractical for large spaces and the tracer gas technique uses chemicals that can be hazardous. An innovative remote air leakage technique namely, beamforming using phased array, is proposed in this thesis. It is fast, compact and economical compared to methods like blower door and tracer gas which are both time consuming and require a lot of resources. It is important to validate our approach by some preliminary experiments and to benchmark these against the \real building" experimental data. We perform tests to compare the present state-of-the-art technique i.e., the blower door test with our proposed remote detection method of using acoustic phased array to detect air in ltration. To resolve sources at low frequency and get better beamform maps, subwoofers are used. Detailed description of the technique along with details of the experimental setup and discussion of results are presented in this thesis.