- Author
- Ingason, H.
- Title
- Investigation of Thermal Response of Glass Bulb Sprinklers Using Plunge and Ramp Tests.
- Coporate
- Lund Univ., Sweden
- Journal
- Fire Safety Journal, Vol. 30, No. 1, 71-93, February 1998
- Report
- Paper 1, 1996, 20 p.
- Keywords
- sprinklers | thermal response | thermal behavior | wind tunnels | thermal analysis | temperature | computer simulation | time lag
- Abstract
- The thermal behvaior of glass bulb sprinklers was investigated in a heated wind tunnel under various test conditions. The response parameters considered were the Response Time Index (TRI), the Conduction parameter (C) and the Change of Phase Parameter (CHP). Combinations of one, two and three response parameters were used to predict the response times of various wind tunnel test conditions, and for slow, medium and fast growth rate fires. These calculations indicate that the wind tunnel results cannot be fully explained in the frameowrk of the thermal response models applied. Tests with a high precondition temperature of the sprinkler resulted in higher RTI values compared with cases with normal precondition temperatures. A plausible explaination for the higher RTI values could be a time delay caused by temperature gradients within the glass bulb. This indicates that the CHP parameter previously explained in terms of work needed to shatter the glass bulb, more likely reflects an affect of thermal time delay.