Generalization of flow regularity of fresh mortar for its implementation to the flow simulation and theoretical extension to rheology
Project/Area Number |
16H02354
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Research Category |
Grant-in-Aid for Scientific Research (A)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Civil engineering materials/Construction/Construction management
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Research Institution | The University of Tokyo |
Principal Investigator |
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Project Period (FY) |
2016-04-01 – 2019-03-31
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Project Status |
Completed (Fiscal Year 2019)
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Budget Amount *help |
¥45,110,000 (Direct Cost: ¥34,700,000、Indirect Cost: ¥10,410,000)
Fiscal Year 2018: ¥13,910,000 (Direct Cost: ¥10,700,000、Indirect Cost: ¥3,210,000)
Fiscal Year 2017: ¥13,910,000 (Direct Cost: ¥10,700,000、Indirect Cost: ¥3,210,000)
Fiscal Year 2016: ¥17,290,000 (Direct Cost: ¥13,300,000、Indirect Cost: ¥3,990,000)
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Keywords | セメント・コンクリート / 流動速度分布 / せん断速度 / レオロジー / 減衰 / ビンガム流体 / 流動 / コンクリート / フレッシュモルタル / ビンガム流動 |
Outline of Final Research Achievements |
In this study, various velocity profiles of different viscous fluids obtained by using MRI technique at different rpm values are analytically analyzed to find the flow regularity and understand the shear stress reduction mechanism in Couette flows. Initially, the Newtonian region was identified in some velocity profiles of Non-Newtonian fluids near the rotor and the Newtonian velocity equation is applied to exclude the Newtonian region from the whole sheared region to identify the rest of Non-Newtonian region present. Subsequently, it was found that this remaining Non-Newtonian region found in almost 50 velocity profiles can be either fitted by the quadratic equation or the cubic equation. This indicates that there exists a simple and clear mechanisms for the shear stress reduction and the energy dispersion during the shear transfer in Couette flows, which are represented by the differential of these velocity functions.
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Academic Significance and Societal Importance of the Research Achievements |
どろどろの流体の科学と称されるレオロジーでは、粘度が主たる興味の対象であるが、MRIを用いて計測されたスラリー等の既存の流動速度分布のデータを詳細に分析した結果、全ての流動速度分布は2次関数もしくは3次関数の何れかで近似できることと、流体のせん断応力伝達には比較的単純で明確な減衰メカニズムが存在することを明らかにしたことの学術的意義は高い。また、広い空間では、力のつり合いが成立しナビエ・ストークス方程式が適用できる水に代表されるニュートン流体の流動も、狭小空間中では極めて高い粘性を示すことから、本研究で明らかにした流動の一般的な規則性の中に特殊な理想形態として包含される可能性が指摘できる。
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Report
(4 results)
Research Products
(4 results)