火災プルームの巨視的性状に関する研究 A Study on the Deterministic Properties of Fire Plumes

この論文にアクセスする

この論文をさがす

著者

抄録

火災プルームは,連続火炎域・間欠火炎域・プルーム域の3つに分けられ,これらの領域に関しては2つの定義の仕方が提示されている。すなわち,火炎高さ,または中心軸上の温度・流速などに基づく定義法であるが,これら相互の関連性は明確ではなく,火炎高さおよび点火源上のプルームに関する古典的理論から導かれる式の次元についても整合性がとれていない。<br>本研究は,既往の研究成果を基に考察して,仮想点源位置を決定できるモデルを提案し,LNGとLPGを用いた拡散火炎実験で検証した結果,火炎高さおよび中心軸上温度による境界が相互によく一致していることを確認し,併せて火炎高さの検討を行ったものである。<br>(オンラインのみ掲載)

A lot of studies on fire plumes formed above fire sources have been carried out in the field of building fire analyses. There are two methods to define the boundaries of continuous, intermittent and plume regions of turbulent diffusion flames. One is to be decided from flame height. And the other is to be decided from the properties of fire plumes on the basis of the classical theory on the point-source plumes. The relationship between them had been ambiguous, and we proposed the following models of virtual source locations resulted from the past experimental works [15-18]: <br>z<sub>0</sub> = (γ − α<sup>2/5</sup>C')Q*<sup>2/5</sup>D (Q* ≧ 1), <br>z<sub>0</sub> = γQ*<sup>2/3</sup>D − α<sup>2/3</sup>C'Q*<sup>2/5</sup>D (0.1 < Q* < 1) <br>In order to ensure these models, several experiments were performed by using 0.14 m or 0.2 m square burner with LPG or LNG fuels. Flame heights were recorded by video tape recorder, and the centerline temperatures and velocities were recorded for 5 minutes at 5 seconds interval in a steady state. <br>As the results, the flame heights were formulated as Lf=γQ*<sup>n</sup>D, where n=2/5 for Q* ≧ 1, and n=2/3 for 0.4 < Q* < 1. And γ equals 3.30 for the mean heights, 4.40 for the boundary height between intermittent flame region and plume region, and 2.10 for the boundary height between flame region and intermittent flame region for calculating z<sub>0</sub>. According to these results, excess temperatures and velocities were plotted above along the central axis of fire plumes. It was found that the boundaries decided both from flame heights and from excess temperatures had been in agreement with each other.

収録刊行物

  • 日本火災学会論文集  

    日本火災学会論文集 44(1), 25-37, 1996-04-30 

    Japan Association for Fire Science and Engineering

参考文献:  32件

参考文献を見るにはログインが必要です。ユーザIDをお持ちでない方は新規登録してください。

各種コード

  • NII論文ID(NAID)
    10002685883
  • NII書誌ID(NCID)
    AN0018688X
  • 本文言語コード
    JPN
  • 資料種別
    ART
  • ISSN
    05460794
  • NDL 記事登録ID
    3975198
  • NDL 雑誌分類
    ZN1(科学技術--建設工学・建設業)
  • NDL 請求記号
    Z16-105
  • データ提供元
    CJP書誌  NDL  J-STAGE 
ページトップへ