Investigation of CO2 tracer gas-based calibration of multi-zone airflow models

Steven C. Snyder, T Agami Reddy, William P. Bahnfleth

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

This paper proposes a methodology to calibrate multizone airflow models in existing buildings. The methodology has been demonstrated with the widely used multi-zone model CONTAM and applied to two buildings, one synthetic and one actual. The methodology builds on previous workwith thecalibration process enhanced by the use of carbon dioxide tracer gas test data. A key concept highlighted in this paper is that calibration of airflow models is a highly over-parameterized problem and that some form of model reduction is imperative. This is achieved by performing an airflow-based sensitivity analysis to identify influential system drivers, a tracer gasbased sensitivity analysis to identify macro-zones (i.e. groups of rooms that can be combined into one zone for the purposes of predicting or studying dynamic airflow behavior under different types of stimuli), and finally, a process of tuning the model parameters. It is found that for mechanically ventilated commercial buildings, calibrating multi-zone models by reconciling differences between measured and predicted tracer gas behavior is more strongly impacted by those factors which significantly influence room air change rates than by airflow path leakage parameter tuning.

Original languageEnglish (US)
Title of host publicationASHRAE Transactions
Pages698-710
Number of pages13
Volume118
EditionPART 2
StatePublished - 2012
Event2012 ASHRAE Annual Conference - San Antonio, TX, United States
Duration: Jun 23 2012Jun 27 2012

Other

Other2012 ASHRAE Annual Conference
CountryUnited States
CitySan Antonio, TX
Period6/23/126/27/12

Fingerprint

Calibration
Gases
Sensitivity analysis
Tuning
Leakage (fluid)
Macros
Carbon dioxide
Air

ASJC Scopus subject areas

  • Mechanical Engineering
  • Building and Construction

Cite this

Snyder, S. C., Reddy, T. A., & Bahnfleth, W. P. (2012). Investigation of CO2 tracer gas-based calibration of multi-zone airflow models. In ASHRAE Transactions (PART 2 ed., Vol. 118, pp. 698-710)

Investigation of CO2 tracer gas-based calibration of multi-zone airflow models. / Snyder, Steven C.; Reddy, T Agami; Bahnfleth, William P.

ASHRAE Transactions. Vol. 118 PART 2. ed. 2012. p. 698-710.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Snyder, SC, Reddy, TA & Bahnfleth, WP 2012, Investigation of CO2 tracer gas-based calibration of multi-zone airflow models. in ASHRAE Transactions. PART 2 edn, vol. 118, pp. 698-710, 2012 ASHRAE Annual Conference, San Antonio, TX, United States, 6/23/12.
Snyder SC, Reddy TA, Bahnfleth WP. Investigation of CO2 tracer gas-based calibration of multi-zone airflow models. In ASHRAE Transactions. PART 2 ed. Vol. 118. 2012. p. 698-710
Snyder, Steven C. ; Reddy, T Agami ; Bahnfleth, William P. / Investigation of CO2 tracer gas-based calibration of multi-zone airflow models. ASHRAE Transactions. Vol. 118 PART 2. ed. 2012. pp. 698-710
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