Computer Simulation of Flow Behaviors of Concentrated Suspensions

浓悬浮液流动行为的计算机模拟

• 批准号: 63550670
• 负责人: DOI Masao
• 金额: $ 1.22万
• 依托单位: Nagoya University (1989)Tokyo Metropolitan University (1988)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1988
• 资助国家: 日本
• 起止时间: 1988 至 1989
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-63550670/
• 关键词: Colloids; Suspension; Emulsion; Concentrated suspension; Computer simulation; Non Newtonian viscosity; 濃原分散系; 非線形粘性; コロイド; 計算機シミュレーション; 濃厚コロイド系; レオロジー; ゲル化

Concentrated suspensions show complex rheological properties, such as thixotropy and rheopexy. According to traditional colloid science, these behaviors are caused by a certain change of internal "structure". However, basic questions such as what kind of "structure" is actually formed, and how it is related to rheological properties have not been answered clearly. In this project, I studied the structure of concentrated suspension in shear flow by computer simulation.Two systems are studied, the hard sphere system and the aggregating system. In the former case, the hydrodynamic interaction is important, and in the latter, the cohesive force between the touching colloids is essential. For each case, a new model is proposed to enable the simulation. The detailed information on the structure and the macroscopic rheological. properties are obtained. A particularly interesting result is that in the aggregating sphere system, the spheres form an infinitely large network when the concentration exceeds a certain critical concentration, but the viscosity remains finite. This indicates that the size of the aggregate is the key factor in determining the viscosity.As a byproduct of the present research, a new theory has been developed on the concentrated emulsions in which the dynamics of interface is important.

浓悬浮液具有复杂的流变特性，如触变性和粘流性。传统胶体科学认为，这些行为是由内部“结构”发生一定变化而引起的。然而，诸如实际上形成了什么样的“结构”，以及它与流变性能如何相关等基本问题尚未得到明确回答。在本项目中，我用计算机模拟的方法研究了剪切流中浓悬浮液的结构，研究了两个体系，硬球体系和聚集体系。在前一种情况下，流体动力学相互作用是重要的，而在后一种情况下，接触的胶体之间的凝聚力是必不可少的。对于每种情况下，提出了一个新的模型，使模拟。详细介绍了其结构和宏观流变性。属性得到。一个特别有趣的结果是，在聚集球系统中，当浓度超过某个临界浓度时，球形成无限大的网络，但粘度保持有限。这表明聚集体的大小是决定粘度的关键因素。作为本研究的副产品，一个新的理论已经发展到浓乳液中的界面动力学是重要的。

项目成果

D.Chen and M.Doi: "Simulation of Aggregating Colloids in Shear Flow II." J.Chem.Phys.91. 2656-2663 (1989)

D.Chen 和 M.Doi：“剪切流中聚集胶体的模拟 II”。

T.Ohta,H.Nozaki and M.Doi: "Computer Simulation of Domain Growth under Steady Shear Flow." J.Chem.Phys.

T.Ohta、H.Nozaki 和 M.Doi：“稳定剪切流下域生长的计算机模拟”。

D. Chen and M. Doi: "Simulation of Aggregating Colloids in Shear Flow II." J. Chem. Phys. 91 2656-2663 1989.

D. Chen 和 M. Doi：“剪切流中聚集胶体的模拟 II”。

M.Doi,D.Chen: "Simulation of Aggregating Colloids in Shear Flow." Frontiers of Macromolecular Science,Blackwell Scientific Pub.313-318 (1989)

M.Doi，D.Chen：“剪切流中聚集胶体的模拟。”

T.Ohta,H.Nozaki and M.Doi: "Computer Simulation of Domain Growth under Steady Shear Flow" Phys.Lett.

T.Ohta、H.Nozaki 和 M.Doi：“稳定剪切流下域生长的计算机模拟”Phys.Lett。