Identification of flow and volume parameters in multizone systems using a single gas tracer technique
Abstract
This work evaluates a new method, based upon tracer gas techniques, for determining interzonal airflows and effective volumes in a multizone enclosure. The proposed method uses a single tracer gas to disturb the zones. A state-space formulation is used to model the multizone system. The concentration data are used in combination with a recursive least-squares identification algorithm to determine all of the interzonal airflows and effective volumes. A three-zone experimental test facility was constructed to validate the proposed method. The results indicate that the gas technique was able to estimate the interzonal airflows and effective volumes of the experimental facility to within 10 percent in most cases. The tests also showed that for a three-zone system, the best accuracy was obtained using a sampling interval, T, in the range 0.1 less than or equal to T/tau(sub min) less than or equal to 0.2. The fastest time constant of the system, tau(sub min), is based upon the airflows and effective volumes of the continuous-time system representation.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- January 1991
- Bibcode:
- 1991STIN...9119368O
- Keywords:
-
- Air Flow;
- Flow Characteristics;
- Mathematical Models;
- Trace Elements;
- Algorithms;
- Differential Equations;
- Mixing;
- Time Constant;
- Fluid Mechanics and Heat Transfer