TY  - JOUR
PY  - 2021//
TI  - Dust explosion characteristics near the minimum explosible concentration
JO  - Journal of the Japan Society for Safety Engineering
A1  - Kuwana, Kazunori
A1  - Kim, Wookyung
A1  - Mogi, Toshio
A1  - Dobashi, Ritsu
SP  - 101
EP  - 108
VL  - 60
IS  - 2
N2  - Minimum explosible concentrations are important safety information concerning dust explosions. This paper presents the results of numerical simulations of dust explosions under conditions close to the minimum explosible concentrations. Dust explosions are modeled as processes of combustion-wave propagation by heat conduction between particles; a particle releases heat when its temperature reaches an ignition temperature. The source term in the heat conduction equation is expressed as the summation of delta functions, enabling the evolution of temperature distribution to be given in terms of fundamental solutions （Greenʼs functions）. In cases of regularly arranged particle configurations, analytical expressions can be obtained for propagation speed and minimum explosible concentration. Numerical simulations were conducted for random particle configurations, reproducing results that are consistent with previous experiments. The influence of particle-size distribution on propagation speed and minimum explosible concentration is additionally studied.     ===    粉塵爆発の下限濃度が物性値やプロセスパラメータにどのように依存するかは，安全工学上重要な問題である．本論文では，粉塵爆発の数値シミュレーションにより得た下限濃度付近の条件における爆発挙動に関する知見を報告する．粒子間の熱伝導により既燃粒子から熱を受けた未燃粒子の温度が着火温度に達することにより燃焼波が伝播するというモデルを採用し，熱伝導方程式の発熱項をデルタ関数で表した．このとき熱伝導方程式の基本解（グリーン関数）を用いて温度分布が得られるため，計算負荷を低減できる（粒子配置が規則的な場合は伝播速度や下限濃度を解析的に求めることができる）．ランダムな粒子配置に対して数値シミュレーションを実施し，実験結果と矛盾しない結果を得た．さらに，粒径分布が伝播速度や下限濃度に及ぼす影響についても検討した．<p />  <p>Language: ja</p>
LA  - ja
SN  - 0570-4480
UR  - http://dx.doi.org/10.18943/safety.60.2_101
ID  - ref1
ER  -