Abstract

An open jet wind tunnel with an exit area of 23 ​× ​9 ​m2 has been built to study the behaviors of large-scale pool fires under controlled wind conditions. A series of measurements on the mean and fluctuating wind velocities, using arrays of hot-wire probes and ultrasonic anemometers, were extensively performed in the transverse planes at the leading and trailing edges of the pool (28 ​m and 48 ​m to the exit). The entire pool was located in the potential core of the central jet flow region, and the longitudinal velocity (U) and turbulence intensity (Iu) exhibited acceptable uniform distributions within the two vertical planes. The mean turbulence intensities in the two planes were close to those in the flat open grassland and sea (7%–10%). The longitudinal velocity spectra were in good agreement with the Von Kármán spectrum at all levels, and the onset frequency for isotropy was about 1.5–3.0 ​Hz. In the central flow region, the turbulence dissipation rates (ε) were fitted well by ε ​= ​0.067U2.69Iu1.90, and the best-fit line for the turbulent diffusivity (νt) was νt ​= ​0.21U0.95Iu0.98. The detailed mean flow and turbulence characteristics provided the necessary information for the pool fire tests and numerical model verification.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.