擬似ポテンシャル格子ボルツマン法による典型的な極低温流体の二相流シミュレーションにおける状態方程式の性能評価
Zhaoqi Zheng1, Jiadong Sun1, Yonghua Huang1
1Shanghai Jiao Tong University, Institute of Refrigeration and Cryogenics, Shanghai 200240, China.
Physical review. E
|February 20, 2026
まとめ
高精度な状態方程式は、格子ボルツマン法を用いた極低温流体のシミュレーションを改善します。状態方程式の評価により、液体-蒸気二相流のシミュレーションの安定性と精度が向上します。
科学分野:
- 計算流体力学
- 熱力学
- 極低温工学
背景:
- 擬似ポテンシャル格子ボルツマン(LB)法は、極低温流体の液体-蒸気二相流および相転移のシミュレーションに有利です。
- 既存のLBシミュレーションでは、極低温流体の特性に対する精度が限定的なPeng-Robinson状態方程式がしばしば使用されています。
研究 の 目的:
- 極低温流体のLBシミュレーションにおける様々な状態方程式の性能を熱力学的に評価すること。
- 高精度な状態方程式(ヘルムホルツエネルギー、修正ベネディクト・ウェッブ・ルービン)を従来のそれと比較すること。
主な方法:
- 三重点から臨界点までの全二相領域における状態方程式の比較評価。
- 液体-蒸気共存密度、表面張力、および偽速度の解析。
- LBシミュレーションにおける状態方程式の性能に関する熱力学的考察。
主要な成果:
- 状態方程式の二相領域特性は、シミュレーションの安定性に大きく影響し、しばしば見過ごされる要因です。
- 高精度な状態方程式は、極低温流体のシミュレーションにおいて、その実現可能性と優位性を示しました。
- 液体-蒸気共存密度、表面張力、および偽速度予測における具体的な改善が認められました。
結論:
- 高精度な状態方程式は、極低温流体の正確で安定したLBシミュレーションに不可欠です。
- 状態方程式の選択は、二相流現象の予測に大きな影響を与えます。
- 本研究は、LBモデリングにおける適切な状態方程式の選択のための熱力学的な基礎を提供します。
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