密度の高いサスペンションにおけるダイナミック・シャー・ジャームの直接観察
Ivo R Peters1, Sayantan Majumdar1, Heinrich M Jaeger1
1James Franck Institute, The University of Chicago, Chicago, Illinois 60637, USA.
Nature
|April 5, 2016
まとめ
密度の高いサスペンションは,シア・ジャミングという現象があり,シア・ストレスは,シア・レートではなく,液体のような状態と固体のような状態の間の移行を制御します. この研究は動的シア・ジャームの枠組みの下で 安定状態と一時的な行動を統合しています
科学分野:
- 物理学
- 材料科学
- レオロギー
背景:
- 硬い粒子の密度の高いサスペンションは ニュートン式でない振る舞いを示します 剪定加厚化や衝撃による固化などです
- これらの現象は往々にして阻害変遷と関連していますが,既存のモデルは安定状態の流れと一時的な固化と密度の変化を調和させるのに苦労しています.
研究 の 目的:
- 密度の高いサスペンションの安定状態と一時的な状態の両方を体系的に探求し,シール加厚とジャームを接続する.
- 粒子の密度,シアストレスの関係と,密度の高い懸浮物における阻害の移行を説明する統一的な枠組みを確立する.
主な方法:
- 安定状態と一時的なレジムの間の密度の高いサスペンションの実験調査.
- 切断阻害フロントの直接追跡
- 粒子密度の系統的な変化と,適用された切断ストレス.
主要な成果:
- 完全に詰まった,固体のような状態は,切断を介して,圧縮なしで,一時的な切断-詰め込みフロントを通じて達成することができます.
- 切断速度ではなく,切断ストレスを主要な制御パラメータとして特定しました.
- 粒子の密度とスイヤーストレスの状態図をマッピングし,不連続のスイヤー加厚を限界的に詰まった状態として識別します.
結論:
- ダイナミック・シャア・ジャミングに基づいた密度の高いサスペンションの動作を統合するフレームワークを開発した.
- 固定状態のシーザー加厚とシーザー阻害プロセスによる一時的な固化.
- 提案された枠組みは,既存の実験データとシミュレーションデータと一致しています.
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