マスード・イブラヒム・アブバカールさん、上野 暢大さん、中本 廉さん、白井克明教授がASME、InterPACK 2025 にて「2025 National Renewable Energy Laboratory Best Paper Award at Interpack 2025」を受賞
2025/11/17
- 地域環境システム専攻
受賞者
マスード イブラヒム アブバカールさん／Mr. Masud Ibrahim Abubakar（地域環境システム専攻／Regional Environment Systems）
中本 廉さん／Mr. Ren Nakamoto（機械工学専攻／Mechanical Engineering）
白井 克明 教授／Prof. Katsuaki Shirai（工学部／College of Engineering）
指導教員
白井 克明 教授／Prof. Katsuaki Shirai（工学部／College of Engineering）
学会・大会名
学会・大会名
The American Society of Mechanical Engineers (ASME)
The International Technical Conference on Packaging and Integration of Electronic and Photonic Microsystems (InterPACK 2025)
The International Technical Conference on Packaging and Integration of Electronic and Photonic Microsystems (InterPACK 2025)
賞名
2025 National Renewable Energy Laboratory Best Paper Award at Interpack 2025
発表題目
Solid Body Rotation and Implication of Secondary Flow Downstream the Obstruction and Partial Shroud of a Rotating Flow in an Enclosed Corotating System
研究内容
研究目的
回転を伴う流体の流れは幅広い分野で見受けられ、天体物理や惑星大気からタービンやポンプを含む流体機械、人工心臓、ディスク・ドライブまで多岐に渡ります。なかでも情報ストレージ機器のHDD (HDD=Hard Disk Drive) は近年データセンターなどで需要が拡大しています。HDDでは記録密度の更なる向上に向けた技術開発が進む一方で、磁気ヘッド浮上に必要な流体の複雑挙動が高精度の位置決め実現の妨げとなっています。本研究ではHDD内の気流を念頭に、容器内で積層回転円盤に駆動される回転流れに着目しました。従来の軸対称モデルではなく、シュラウド開口部と挿入アームを模擬した非軸対称モデルを提唱して回転流れの複雑挙動を実験的に調査しました。流れの可視化と粒子画像計測法 (PIV=Particle Image Velocimetry) を用いた流速分布の計測を進め、複雑な流れ構造を解析しました。実験結果から、従来の軸対称形状と同様に、非軸対称形状であっても回転円盤間に挿入した模擬アームの上流と下流の領域では二次流れが形成されることを示唆する結果が得られました。さらにハブ近傍で形成される剛体回転に支配される領域が、アーム挿入角度によって変動することを見出しました。これらの解明に基づき、空間的な流れ領域の分類が可能となり、容器内で回転円盤に駆動される流体機器の設計開発における重要な知見が得られました。
Disk-driven flows are fundamental to a wide range of systems, including astrophysical and geophysical flows, turbines and pumps, artificial hearts, and hard disk drives (HDDs). HDDs remain major device for information storage and are widely used for data centers. While development continues toward achieving higher recording densities, complex fluid flows hinder high-precision positioning of the magnetic recording head. In this study, we developed a non-axisymmetric corotating model system featuring an inserted obstruction and a partial shroud opening, in contrast to conventional axisymmetric configurations. A two-dimensional, two-component particle image velocimetry (2D2C PIV) technique was employed to measure and analyse the flow fields. The results revealed the presence of secondary flows both upstream and downstream of the inserted obstruction within the inter-disk planes similar to axisymmetric case. Additionally, solid-body rotation was observed around the hub, with its extent of development depending on the insertion angle of the arm. Based on the flow behaviour, a spatial classification of flow regimes along the streamwise direction was established, providing insights that can contribute to the enhancement of corotating system designs.
Disk-driven flows are fundamental to a wide range of systems, including astrophysical and geophysical flows, turbines and pumps, artificial hearts, and hard disk drives (HDDs). HDDs remain major device for information storage and are widely used for data centers. While development continues toward achieving higher recording densities, complex fluid flows hinder high-precision positioning of the magnetic recording head. In this study, we developed a non-axisymmetric corotating model system featuring an inserted obstruction and a partial shroud opening, in contrast to conventional axisymmetric configurations. A two-dimensional, two-component particle image velocimetry (2D2C PIV) technique was employed to measure and analyse the flow fields. The results revealed the presence of secondary flows both upstream and downstream of the inserted obstruction within the inter-disk planes similar to axisymmetric case. Additionally, solid-body rotation was observed around the hub, with its extent of development depending on the insertion angle of the arm. Based on the flow behaviour, a spatial classification of flow regimes along the streamwise direction was established, providing insights that can contribute to the enhancement of corotating system designs.
研究目的
本研究は情報ストレージ機器のHDDを念頭に、非軸対称形状で積層回転円盤に駆動される回転流れの複雑流れ構造の解明を目指したものです。HDD内の気流に起因する磁気ヘッドの機械的振動がドライブの安定稼働と更なる記録密度向上の妨げとなっています。非軸対称形状の単純化した流れモデルの採用により、HDD内の気流を模擬した調査が可能となり、本研究では特にシュラウド開口部とアーム挿入下での流れ領域の分類に取り組みました。
The objective is to enhance the development of non-axisymmetric disk-driven flow models, such as those found in HDDs. In HDDs, flow-induced mechanical vibrations in the head flying height can increase the risk of read/write errors, thereby limiting further advancements in recording density. Since simplified models provide a fundamental benchmark for understanding disk-driven flows in corotating systems, this research aims to establish a spatial classification of flow regions along the streamwise direction of an inserted obstruction.
今後の展望
The objective is to enhance the development of non-axisymmetric disk-driven flow models, such as those found in HDDs. In HDDs, flow-induced mechanical vibrations in the head flying height can increase the risk of read/write errors, thereby limiting further advancements in recording density. Since simplified models provide a fundamental benchmark for understanding disk-driven flows in corotating systems, this research aims to establish a spatial classification of flow regions along the streamwise direction of an inserted obstruction.
今後の展望
非軸対称形状を有する容器内で積層回転円盤によって駆動される流れは、非定常で三次元性を伴う複雑な流れ挙動を示します。本研究ではHDD内の気流を念頭にしたものですが、得られた知見はHDDのみならず回転を伴う流体機械の複雑流れの解明と性能向上に広く寄与すると考えられます。今後の研究では、三次元流れの実験的把握と数値解析の併用により、流れ構造の更なる解明が期待されます。
Flows driven by stacked rotating disks within a container with non-axisymmetric geometry exhibit unsteady behavior with complex three-dimensional characteristics. While this study was conducted with the airflow inside HDDs in mind, the findings are expected to contribute more broadly to understanding and improving the performance of fluid machinery involving rotation. Future research is anticipated to further elucidate these unsteady and complex flow structures through a combination of experimental investigation and numerical analysis of three-dimensional flows.
Flows driven by stacked rotating disks within a container with non-axisymmetric geometry exhibit unsteady behavior with complex three-dimensional characteristics. While this study was conducted with the airflow inside HDDs in mind, the findings are expected to contribute more broadly to understanding and improving the performance of fluid machinery involving rotation. Future research is anticipated to further elucidate these unsteady and complex flow structures through a combination of experimental investigation and numerical analysis of three-dimensional flows.
