フラクタル記述の相互関係と,渦巻性プレミックス炎の3Dと2Dの炎の比率について
Nilanjan Chakraborty1, Markus Klein2
1Newcastle University, Newcastle Upon Tyne, UK.
まとめ
新しいスケーリング関係は,炎の表面のフラクタル次元と3Dと2Dの表面面積の比率を結びつける. この方法は,渦巻のプレミックスした炎の炎の折りたたみ因子を正確に予測します.
科学分野:
- * 燃焼科学
- * 流体力学
- * フラクタル幾何学
背景:
- 燃焼研究において,複雑な炎の表面の特徴づけは極めて重要です.
- * フラクタル寸法とび率は,炎の表面の複雑さの重要な指標です.
- * 以前の方法はしばしば直接の3D測定に頼っていたが,これは困難だった.
研究 の 目的:
- * 炎の表面のフラクタル次元のための新しいスケーリング関係を導出し,検証する.
- * 3Dの炎の表面積と2Dの表面積とフラクタル次元との関係を確立する.
- * 直接数値シミュレーション (DNS) データを用いて,この関係の正確さを評価する.
主な方法:
- * 同位方角分布の仮定に基づくスケーリング関係の導出
- 既存のDNSデータベースを利用した.
- * カーロビッツ数値の範囲にわたる炎を分析した.
主要な成果:
- * 派生したスケーリング関係は,薄い反応領域に対して妥当な精度を示している.
- * 予測の精度は,カーロビッツ数を増やすことで改善されます.
- * 2D測定により,高カルロビッツ数で3Dのび因子を予測できます.
- * 3Dと2Dの縮因子の比は,3Dのフラクタル次元を推定する.
結論:
- * 新しいスケーリング関係は,特に高カルロビッツ数で,フラクタル次元を推定する別の経路を提供します.
- * 発見は,薄い反応領域のシステムにおける渦巻のプレミックス炎に特に関連しています.
- * この研究は,3Dの炎の特徴を予測するための2D測定の使用を検証しています.
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