Innovative study toward prediction of friction drag at rough surfaces based on the investigation of the turbulent transport mechanisms by the volume averaging theory

• Project/Area Number: 17K14591
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Fluid engineering
• Research Institution: Osaka Prefecture University
• Principal Investigator: Yusuke Kuwata 大阪府立大学, 工学(系)研究科(研究院), 助教 (40772851)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000); Fiscal Year 2020: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2019: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2018: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2017: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
• Keywords: 粗面乱流 / 乱流モデル / 直接数値解析 / 空間・時間平均系 / 格子ボルツマン法 / 空間平均理論 / 空間・レイノルズ平均 / 乱流粗面 / 二重平均系

Outline of Final Research Achievements

Two types of the mathematical model are developed to predict friction drag at a rough surface by means of the direct numerical simulations by the supercomputer. Both models do not resolve the microscopic roughness structure but take account of the macroscopic effects by the wall roughness. One of the models predicts turbulence near a rough surface without resolving the roughness geometry. The other predicts a mean flow near a rough surface without resolving a time-dependent turbulent flow nor roughness geometry. It is confirmed that both models can accurately predict friction drag for various types of rough surfaces.

Academic Significance and Societal Importance of the Research Achievements

実在する壁面は表面に生じる粗さの影響を受けるために，流体力学的な理想的滑面とみなすことができない場合が多い．しかし，その粗さの形状は様々であり，汎用的に粗さ効果を予測することは一般的に難しい．本研究では，粗さ高さに関する幾何パラメータを用いる既往の代数的なモデルでは無く，モデル化された粗さ効果を含んだ流動方程式を解くモデルを提案した．本モデルは，既往モデルとは大きく異なり，様々な流動条件・粗さ形状に対して汎用的に使用することができる．

Research Products

• [Journal Article] Direct numerical simulation of turbulent conjugate heat transfer in a porous-walled duct flow (2020)
  • Author(s): Yusuke Kuwata, Koji Tsuda, Kazuhiko Suga
  • Journal Title: Journal of Fluid Mechanics Volume: 904
  • DOI: 10.1017/jfm.2020.669
  • NAID: 120006938352
  • Peer Reviewed
• [Journal Article] Direct numerical simulation on the effects of surface slope and skewness on rough-wall turbulence (2020)
  • Author(s): Yusuke Kuwata, Rika Nagura
  • Journal Title: Physics of Fluids Volume: 32(10) Issue: 10 Pages: 105113-105113
  • DOI: 10.1063/5.0024038
  • NAID: 120006938351
  • Peer Reviewed
• [Journal Article] On the scaling of turbulence over an irregular rough surface in a transitionally rough regime (2020)
  • Author(s): Yusuke Kuwata, Takuya Sugiyama, Yasuo Kawaguchi
  • Journal Title: Journal of Thermal Science and Technology Volume: 15 Issue: 2 Pages: JTST0015-JTST0015
  • DOI: 10.1299/jtst.2020jtst0015
  • NAID: 130007883977
  • ISSN: 1880-5566
  • Peer Reviewed
• [Journal Article] An extension of the second moment closure model for turbulent flows over macro rough walls (2019)
  • Author(s): Yusuke Kuwata, Kazuhiko Suga, Yasuo Kawaguchi
  • Journal Title: International Journal of Heat and Fluid Flow Volume: 77 Pages: 186-201
  • DOI: 10.1016/j.ijheatfluidflow.2019.04.003
  • NAID: 120006782457
  • Peer Reviewed
• [Journal Article] Direct numerical simulation of turbulence over resolved and modeled rough walls with irregularly distributed roughness (2019)
  • Author(s): Yusuke Kuwata, Yasuo Kawaguchi
  • Journal Title: International Journal of Heat and Fluid Flow Volume: 77 Pages: 1-18
  • DOI: 10.1016/j.ijheatfluidflow.2019.02.009
  • NAID: 120006894177
  • Peer Reviewed
• [Journal Article] Direct numerical simulation of turbulence over systematically varied irregular rough surfaces (2019)
  • Author(s): Yusuke Kuwata, Yasuo Kawaguchi
  • Journal Title: Journal of Fluid Mechanics Volume: 862 Pages: 781-815
  • DOI: 10.1017/jfm.2018.953
  • NAID: 120006894179
  • Peer Reviewed
• [Journal Article] Statistical discussions on skin frictional drag of turbulence over randomly distributed semi-spheres (2018)
  • Author(s): Yusuke Kuwata, Yasuo Kawaguchi
  • Journal Title: International Journal of Advances in Engineering Sciences and Applied Mathematics Volume: 10 Issue: 4 Pages: 263-272
  • DOI: 10.1007/s12572-018-0223-z
  • NAID: 120006894178
  • Peer Reviewed
• [Presentation] An investigation of the influence of rough surface char- acteristics on turbulent heat transfer (2021)
  • Author(s): Yusuke Kuwata, Shinya Tabata
  • Organizer: Turbulence, Heat and Mass Transfer 10
  • Int'l Joint Research
• [Presentation] Direct numerical simulation on the influence of slope and skewness of turbulent flows over irregular rough surfaces (2021)
  • Author(s): Yusuke Kuwata
  • Organizer: 13th International ERCOFTAC Symposium on Engineering Turbulence Modelling and Measurements
  • Int'l Joint Research
• [Presentation] SCALING OF TRANSIOTIONAL ROUGH WALL TURBULENT FLOW OVER IRREGULAR ROUGH SURFACE (2019)
  • Author(s): Yusuke Kuwata, Takuya Sugiyama, Yasuo Kawaguchi
  • Organizer: The 7th Asian Symposium on Computational Heat Transfer and Fluid Flow
  • Int'l Joint Research
• [Presentation] DIRECT NUMERICAL SIMULATION OF CONJUGATE TURBULENT HEAT TRANSFER IN POROUS SQUARE DUCT (2019)
  • Author(s): Yusuke Kuwata, Koji Tsuda, Kazuhiko Suga
  • Organizer: 11th International Symposium on Turbulence and Shear Flow Phenomena
  • Int'l Joint Research
• [Presentation] Direct numerical simulation study on the influence of rough surface slope on turbulence (2019)
  • Author(s): Yusuke Kuwata
  • Organizer: Asian Pacific Congress on Computational Mechanics
  • Int'l Joint Research
• [Presentation] 格子ボルツマン法による不規則粗面壁の乱流熱流動解析 (2019)
  • Author(s): 桑田 祐丞
  • Organizer: 第 32 回計算力学講演会
• [Presentation] 多孔体壁矩形ダクトの乱流熱流動解析 (2019)
  • Author(s): 桑田 祐丞，津田 航志，須賀 一彦
  • Organizer: 第 56 回日本伝熱シンポジウム
• [Presentation] 応力方程式モデルによる巨視的粗面乱流モデル (2018)
  • Author(s): 桑田 祐丞，川口 靖夫
  • Organizer: 第55回伝熱シンポジウム
• [Presentation] Macroscopic modelling of rough wall turbulence based on the second moment closure (2018)
  • Author(s): Yusuke Kuwata, Yasuo Kawaguchi, Kazuhiko Suga
  • Organizer: International Symposium on Turbulence, Heat and Mass Transfer 18
  • Int'l Joint Research
• [Presentation] 局所細密格子法を用いた格子ボルツマン法による実在粗面乱流のLES (2018)
  • Author(s): 杉山 琢哉，桑田 祐丞，川口 靖夫
  • Organizer: 第２３回計算工学講演会
• [Presentation] Lattice Boltzmann direct numerical simulation of turbulence over resolved and modelled walls with irregularly distributed roughness (2017)
  • Author(s): Yusuke Kuwata, Yasuo Kawaguchi
  • Organizer: 10th International Symposium on Turbulence and Shear Flow Phenomena
  • Int'l Joint Research
• [Presentation] Lattice Boltzmann direct numerical simulation of turbulence over randomly distributed hemispheres (2017)
  • Author(s): Yusuke Kuwata, Yasuo Kawaguchi
  • Organizer: 16th European Turbulence Conference
  • Int'l Joint Research
• [Presentation] Statistical discussions on turbulence around randomly distributed semi-spheres (2017)
  • Author(s): Yusuke Kuwata, Yasuo Kawaguchi
  • Organizer: Asian Symposium on Computational Heat Transfer and Fluid Flow
  • Int'l Joint Research
• [Presentation] 空間平均理論に立脚した粗面モデルによる乱流解析 (2017)
  • Author(s): 桑田 祐丞，川口 靖夫
  • Organizer: 第５４回日本伝熱シンポジウム