Scale Effects on Flame Structure in Pool Fires

• ITO Akihiko

  Department of Intelligent Machines and System Engineering, Hirosaki University

• KUDO Yuji

  Department of Intelligent Machines and System Engineering, Hirosaki University

• SAITO Kozo

  Department of Mechanical Engineering, University of Kentucky

Bibliographic Information

Other Title

• プール火災の火炎構造に及ぼすスケール効果
• プール カサイ ノ カエン コウゾウ ニ オヨボス スケール コウカ

Abstract

Experiments using a particle-track laser sheet technique (PTLS) and a laser sheet tomography (LST) combined with a high speed video camera are conducted to reveal the flame structure and the flow vector diagram in pool fires. To improve our understanding of the scale effects on buoyancy controlled flame structure, we employed four different size of kerosene pool fire whose pan diameters are 10, 20, 30 and 50 cm. These results were compared with the numerical analysis previously presented by other researchers. The flow visualization results at the vertical plane along a center axis are in good agreement with the numerical results. However, air entrainment through the flame is estimated to be at most 20% larger than that of axisymmetric smooth flame because of the increase of the reaction surface area and the existence of the rotational velocity component around the wrinkled flame. For a medium-size pool fire below a 20 cm-diameter pan, the flame height and the puffing frequency are close to an assembled small-size pool fires in which 3 cm-diameter pans are lined around circle. The flame structure below a 20 cm-diameter pool fire seems to be composed of several flame cells. While the flame structure above a 30 cm-diameter pan is quite different from the aggregate of small-size pool fires. For a 50 cm-diameter pool fire wrinkled flame having high frequent disturbance of 12-14 Hz occurs near the base flame zone and grows along the flame surface. A pool fire beyond a 50 cm-diameter pan transits to a large-scale pool fire having turbulent flow structure.

Journal

• Bulletin of Japan Association for Fire Science and Engineering

  Bulletin of Japan Association for Fire Science and Engineering 54 (1), 9-16, 2004

  Japan Association for Fire Science and Engineering

Details

• CRID: 1390282680924543360
• NII Article ID: 10012124754
• NII Book ID: AN0018688X
• DOI: 10.11196/kasai.54.1_9
• ISSN: 18835600
• ISSN: 05460794
• NDL BIB ID: 6874156
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I6874156
• Text Lang: en
• Data Source:
  • JaLC
  • NDL
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed