深層コンベクションの混合長理論の妥当性テスト

K L Chan, S Sofia

Science (New York, N.Y.)

|January 23, 1987

まとめ

この研究は,3Dシミュレーションを用いた恒星コンベクションの混合長理論を検証しています. 結果は,コンベクティブフロースを正確に近似することができ,太陽と恒星モデルの構築を助けることを示しています.

科学分野:

天体物理学天体物理学
計算式流体力学について
星の天体物理学星の天体物理学

背景:

コンベクティブフロースの正確な計算は,太陽と恒星のモデルにとって非常に重要です.
広く用いられている混合長理論のコンベクションには,実験的または計算的検証が欠けている.
恒星の内部にある不安定な領域は,コンベクションのモデル化に課題をもたらす.

研究の目的:

混ぜる長さのコンベクション理論の妥当性をテストするために.
恒星モデルにおけるコンベクティブフルス計算の物理的精度を調査する.
太陽と恒星のモデリングの改善のための計算基盤を提供すること.

主な方法:

深層で効率的なコンベクションの3次元数値シミュレーションを行いました.
分析された流体要素の動きと,その相関関係と圧力スケールの高さ.
層格構造に基づくコンベクティブフクスを含む,計算された動的変数.

主要な成果:

混合長理論の基本的な物理的イメージは,シミュレーションによってサポートされています.
流体要素の運動の垂直相関は,圧力スケールの高さに比例する.
流動的流量やその他の動的変数は,混合長近似を用いて近似することができます.

結論:

混合長理論は,コンベクションをモデル化するための物理的に有効な枠組みを提供します.
数値シミュレーションは,コンベクティブフルーツの計算のための混合長近似の有用性を確認しています.
この研究は,コンベクション理論を検証することによって,太陽と星のモデルの精度を高めています.

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