- 著者
- 胡 長洪 福地 信義 中島 徹
- 出版者
- 公益社団法人日本船舶海洋工学会
- 雑誌
- 日本造船学会論文集 (ISSN:05148499)
- 巻号頁・発行日
- no.189, pp.127-135, 2001-06
In many compartment natural-convection problems associate with functional design of beat transfer for ships and ocean structures, large temperature difference occurs between the surrounding walls. Examples of such heat transfer problems include a cabin of a passenger ship when the neighboring cabin is on fire, and reefer holds of a refrigerating cargo ship. In these situations, heat radiation exchange among the wall surfaces cannot be neglected if the wall emissivities are not very small. In this paper, a numerical study is reported on combined turbulent convection, heat radiation and conduction in a rectangular enclosure with all six surrounding walls having finite emissivity and conductance. The turbulent convection is computed by a large eddy simulation (LES) method. The emphasis of the study is on the effects of wall radiation exchange on turbulent natural convection in a rectangular enclosure. For comparison with the computation, a laboratory experiment is also carried out on a rectangular enclosure with one sidewall heated by electric heaters. The effect of wall radiation on the natural convection is investigated by changing the wall emissivities. Excellent agreement of temperature between numerical predictions and the experimental measurements is obtained.
1 0 0 0 OA 緊急時の心理過程と歩行モデルによる避難行動の解析
- 著者
- 福地 信義 小山 清文 篠田 岳思
- 出版者
- The Japan Society of Naval Architects and Ocean Engineers
- 雑誌
- 日本造船学会論文集 (ISSN:05148499)
- 巻号頁・発行日
- vol.1999, no.186, pp.545-558, 1999 (Released:2009-09-04)
- 参考文献数
- 13
- 被引用文献数
- 4 3
In the safety design of marine systems, it has to justly give a matter over human life in the case of outbreak of a marine accident such as fires and collisions. It may be difficult to establish a safe evacuation system by the cause of uncertain behavioral patterns based on human factors with ambiguity. Besides, the psychological effect on behavior of evacuee that is terrified under the stimulus by accident, should be considered in the redundancy system for safe evacuation. Accordingly, the safe evacuation system with the intention of securing evacuation routes and reducing escape time, is desirably designed by grasping the personnel behavior with psychological intelligence process in an emergency of marine accident.In this paper, the evacuation behaviors can be predicted by using the proposed walking model with individual capacity of visible length and avoidance process for obstacles. Further, the mathematical model of psychological intelligence process in an emergency is contrived herein, in which the evacuation movement is simulated in the consideration of the decrease of walking speed and the occurrence of self-isolation in psychological action according to the magnitudes of accident stimulus. By applying these models to common spaces in a dinning cruise ship, taking account of the human factors with psychological action is rather valued in the safe evacuation system and the validity of the proposed models can be confirmed.
軽量構造船は構造材がアルミ合金であるため、火災時には溶融・発熱燃焼が起こる危険性があり、軽量構造船特有の防火対策が不可欠である。このため、アルミ合金の船における火災伝播現象のシミュレーションと防火対策の等価性評価のための評価法の提案を行った。主な研究成果は次の通りである。(1)火災伝播現象シミュレーションのための数学モデル軽量構造船を対象に、火災時に破損孔を生じる可能性のある場合について火災伝播の様相を調べるために、火災現象の状態方程式と船内区画をリニアグラフで結合によりモデル化し、可燃物の燃焼特性、ガスの発生、熱および気流に関する状態方程式により火災現象の数学モデルを構築した。これにより火災伝播現象の数値シミュレーションのための計算法を確立した。(2)軽量構造船の火災伝播状態形状を簡易化した3層甲板客船モデルおよび単胴型高速船の延焼状態について計算を行い、壁体の破損温度、防熱材厚さおよび火災荷重と火災拡大の関係を明らかにした。また、壁体に破損が起こる場合の火災の拡大要因は、破損孔による酸素補給の有無と熱移流であり、防火構造の防熱性能と耐熱強度が問題であること、特に発火区画での火災減退期までの熱封鎖の可否が火災拡大の分岐条件となることを示した。(3)防火対策の等価性評価のための手法評価対象を評価する際に、代替項目により優れた特徴のみを問題視する代替的評価と欠点のないものを選好する補完的評価がある。このような多面性問題に対して、評価選好基準にBelief測度あるいはPlausibi-lity測度のようなFuzzy測度を用いた多基準分析法による代替性・補完性評価の手法を提案した。