The calculation of the heat release rate by oxygen consumption in a controlled-atmosphere cone calorimeter

• Published in: Fire and materials Vol. 38; no. 2; pp. 204 - 226
• Main Authors: Werrel, Martin, Deubel, Jan H., Krüger, Simone, Hofmann, Anja, Krause, Ulrich
• Format: Journal Article
• Language: English
• Published: Chichester Blackwell Publishing Ltd 01.03.2014; Wiley; Wiley Subscription Services, Inc
• Subjects: Applied sciences; Building technical equipments; Buildings; Buildings. Public works; Computation methods. Tables. Charts; cone calorimeter; controlled-atmosphere cone calorimeter; Exact sciences and technology; excess air; Fire behavior of materials and structures; Fire protection; heat release rate; Measurements. Technique of testing; oxygen consumption; Structural analysis. Stresses; vitiation and ventilation control; controlled-atmosphere cone calorimeter; Calorimeter; vitiation and ventilation control; excess air; Oxygen consumption; Experimental device; Controlled atmosphere; Heat liberation; cone calorimeter; Fire test; Ventilation; Application; Computing method; heat release rate
• ISSN: 0308-0501; 1099-1018
• DOI: 10.1002/fam.2175

ABSTRACT The standard cone calorimeter according to ASTM E 1354 and ISO 5660 enables reaction‐to‐fire tests to be performed in ambient atmospheric conditions. A controlled‐atmosphere chamber modifies the standard apparatus in a way that allows tests to be performed in nonambient conditions as well. The enclosed chamber is placed underneath the standard exhaust hood and does not have a closed connection to the hood. With this open arrangement, the exhaust gases are diluted by excess air drawn in from the laboratory surroundings. Heat‐induced changes in the consequential dilution ratio affect the calculation of fire quantities and, when neglected, lead to deviations of up to 30% in heat release rate. The paper introduces a test protocol and equations to calculate the heat release rate taking dilution effects into account. A mathematical correction is shown that compensates for the dilution effects while avoiding extensive mechanical changes in the equipment. Copyright © 2013 John Wiley & Sons, Ltd.