IN-91-18-2 -- Performance and Comparison of Tracer Gas Methods for Measuring Air Flows in Two-Zone Buildings PDF

Discusses three methods for measuring interzonal air movement in two-zone buildings - the initial injection of one tracer into a single room, repeated injection of one tracer into two rooms, and initial injection of two tracers in two rooms. Theoretical analyses for each of these methods are presented. Error analyses and numerical simulations demonstrate the different performances of the methods under investigation. For the purpose of testing the accuracy of the above methods, a laboratory-scale physical model with two chambers has been built. The model is equipped with pumps and flowmeters that establish and measure every desired air movement. Comparisons of experimentally established air flows with evaluation results from the above-mentioned tracer gas methods are performed. Results show that method 1 is very sensitive to measurement noise and therefore inferior to methods 2 and 3. Methods 2 and 3 both yield satisfactory results. While method 2 requires less tracer gas equipment than method 3, it needs longer periods of measurement to achieve the same accuracy.

KEYWORDS: performance, comparing, tracers, gas, measuring, buildings, air movement, rooms, calculating,testing, accuracy, laboratory testing, air flow, air flow rate, zones