Deep convection and dynamo action of giant planet.

• Project/Area Number: 25800273
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Space and upper atmospheric physics
• Research Institution: Kyoto University
• Principal Investigator: SASAKI Youhei 京都大学, スーパーグローバルコース数学系ユニット, 特定助教 (70583459)
• Project Period (FY): 2013-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000); Fiscal Year 2016: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2015: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2014: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2013: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
• Keywords: 木星型惑星 / ダイナモ作用 / 数値モデル / 深部対流 / 回転球殻対流 / 圧縮性流体 / MHDダイナモ / 巨大惑星 / 縞状構造 / 非弾性方程式系

Outline of Final Research Achievements

Numerical model for MHD in rotating sphericall shells is developed. Linear stability analysis of compressible % thermal convection in rotating spherical shells using this numerical model is performed with the anelastic approximation. At large compressibility, the location of convection column is close to the outer boundary, and the convective motion occurs are near the outer boundary. This feature is highly depends radical thermal diffusivity. Numerical experiments of magneto-hydrodynamic dynamo in a rotating spherical shell with a strongly stable outer layer are performed. The proposed theoretical expression of propagation distance of the Alfven waves suggests that the numerically obtained fields permit the complete propagation of the Alfven waves across the stable layer.

Research Products

• [Journal Article] Penetration of steady fluid motions into an outer stable layer excited by MHD thermal convection in rotating spherical shells (2017)
  • Author(s): Takehiro, S., Sasaki, Y.
  • Journal Title: Physics of the Earth and Planetary Interiors Volume: - Pages: 258-264
  • DOI: 10.1016/j.pepi.2017.03.001
  • Peer Reviewed
• [Journal Article] Performance benchmarks for a next generation numerical dynamo model (2016)
  • Author(s): Matsui, H., ... Sasaki, Y., ...他(34名)
  • Journal Title: Geochemistry, Geophysics, Geosystem Volume: 電子出版 Issue: 5 Pages: 1586-1607
  • DOI: 10.1002/2015gc006159
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Full sphere hydrodynamic and dynamo benchmarks (2014)
  • Author(s): Marti, P., Schaeffer, N., Hollerbach, R., Cebron, D., Nore, C., Luddens, F., Guermond, J.-L., Aubert, J., Takehiro, S., Sasaki, Y., Hayashi, Y.-Y., Simitev, R., Busse, F., Vantieghem, S., Jackson, A.
  • Journal Title: Geophysical Journal International Volume: 197 Issue: 1 Pages: 119-134
  • DOI: 10.1093/gji/ggt518
  • Peer Reviewed
• [Journal Article] A spherical shell numerical dynamo benchmark with pseudo-vacuum magnetic boundary conditions (2014)
  • Author(s): Jackson, A., Sheyko,A., Marti, P., Tilgner, A., Cebron, D., Vantieghem, S., Simitev, R., Busse, F., Zhan, X., Schubert, G., Takehiro, S., Sasaki, Y., Hayashi, Y.-Y., Ribeiro, A., Nore, C., Guermond, J.-L.
  • Journal Title: Geophysical Journal International Volume: 196 Issue: 2 Pages: 712-723
  • DOI: 10.1093/gji/ggt425
  • Peer Reviewed
• [Journal Article] Differential Rotation and Angular Momentum Transport Caused by Thermal Convection in a Rotating Spherical Shell (2013)
  • Author(s): Takehiro, S., Sasaki, Y., Hayashi, Y.-Y., Yamada, M.
  • Journal Title: Progress in Physics of the Sun and Stars Volume: 479 Pages: 285-294
  • Peer Reviewed
• [Journal Article] Effects of latitudinally heterogeneous buoyancy flux conditions at the inner boundary on MHD dynamo in a rotating spherical shell (2013)
  • Author(s): Sasaki, Y., Takehiro, S., Nishizawa, S., Hayashi, Y.-Y.
  • Journal Title: Phys. Earth Planet. Inter. Volume: 223 Pages: 55-61
  • DOI: 10.1016/j.pepi.2013.07.003
  • Peer Reviewed
• [Journal Article] 回転球殻内の非弾性流体熱対流の線形安定性 (2013)
  • Author(s): 佐々木 洋平, 竹広 真一, 中島健介, 林祥介
  • Journal Title: ながれ Volume: 32 Pages: 469-472
  • Peer Reviewed
• [Presentation] Mean zonal flows induced by Boussinesq thermal convection in rotating spherical shells as an application to the gas giant planets (2017)
  • Author(s): Takehiro, S., Sasaki, Y., Ishioka, K., Nakajima, K., Hayashi, Y.-Y.
  • Organizer: WTK Aquaplanet Workshop, 21st January 2017
  • Place of Presentation: National Astronomical Observatory of Japan
  • Year and Date: 2017-01-21
  • Invited
• [Presentation] GFD-Dennou Club DCMODEL project (2017)
  • Author(s): Takehiro S., Takahashi, Y. O., Sugiyama, K., Odaka, M., Ishiwatari, M., Horinouchi, T., Sasaki, Y., Ishioka, K., Nakajima, K., Hayashi, Y.-Y.
  • Organizer: WTK Aquaplanet Workshop
  • Place of Presentation: CPS, Kobe University
  • Year and Date: 2017-01-21
  • Invited
• [Presentation] 回転球殻中の磁気対流により引き起こされる平均帯状流の外側安定成層への貫入 (2016)
  • Author(s): 竹広真一, 佐々木洋平
  • Organizer: 2016 年日本流体力学会年会
  • Place of Presentation: 名古屋工業大学 御器所キャンパス
  • Year and Date: 2016-09-26
• [Presentation] 回転球殻内の非弾性熱対流の臨界モードに対する熱拡散係数の動径分布の影響 (2016)
  • Author(s): 佐々木洋平, 竹広真一, 石渡正樹, 山田道夫
  • Organizer: 2016 年日本流体力学会年会
  • Place of Presentation: 名古屋工業大学 御器所キャンパス
  • Year and Date: 2016-09-26
• [Presentation] Penetration of mean zonal flows into an outer stable layer excited by MHD thermal convection in rotating spherical shells (2016)
  • Author(s): Takehiro, S., Sasaki, Y.
  • Organizer: SEDI 2016
  • Place of Presentation: La Cite Nantes Events Center, France
  • Year and Date: 2016-07-24
• [Presentation] Critical mode of anelastic thermal convection in a rotating spherical shell depends on radial distribution of thermal diffusivity (2016)
  • Author(s): Sasaki, Y., Takehiro, S., Ishiwatari, M., Yamada, M.
  • Organizer: SEDI 2016
  • Place of Presentation: La Cite Nantes Events Center, France
  • Year and Date: 2016-07-24
• [Presentation] 高速回転する薄い球殻内の熱対流により生成される表層縞状構造への 力学的境界条件の影響 (2016)
  • Author(s): 佐々木洋平, 竹広真一, 石岡圭一, 中島健介, 林祥介
  • Organizer: 2016 年日本気象学会春季大会
  • Place of Presentation: 国立オリンピック記念青少年総合センター
  • Year and Date: 2016-05-25
• [Presentation] 回転球殻中の磁気対流により引き起こされる平均帯状流の 外側安定成層への貫入 (2016)
  • Author(s): 竹広真一, 佐々木洋平
  • Organizer: 日本地球惑星科学連合 2016 年大会
  • Place of Presentation: 幕張メッセ国際会議場
  • Year and Date: 2016-05-20
• [Presentation] 高速回転する薄い球殻内の熱対流により生成される表層縞状構造への 力学的境界条件の影響 (2016)
  • Author(s): 佐々木洋平, 竹広真一, 石岡圭一, 中島健介, 林祥介
  • Organizer: 日本地球惑星科学連合 2016 年大会
  • Place of Presentation: 幕張メッセ国際会議場
  • Year and Date: 2016-05-20
• [Presentation] 高速回転する薄い球殻内の熱対流により引き起こされる表層縞状構造の消滅 (2015)
  • Author(s): 佐々木洋平, 竹広真一, 石岡圭一, 中島健介, 林祥介
  • Organizer: 日本流体力学会年会
  • Place of Presentation: 東京工業大学 大岡山キャンパス
  • Year and Date: 2015-09-25
• [Presentation] Penetration of magneto-hydrodynamic disturbances into a strongly stable outer layer caused by MHD dynamo in a rotating spherical shell, (2015)
  • Author(s): Sasaki, Y., Takehiro, S.
  • Organizer: Japan SEDI symposium
  • Place of Presentation: Earthquake Research Institute, University of Tokyo
  • Year and Date: 2015-09-24
• [Presentation] 高速に回転する薄い球殻内の熱対流により引き起こされる表層縞状構造の消滅 (2015)
  • Author(s): 佐々木洋平, 竹広真一, 石岡圭一, 中島健介, 林祥介
  • Organizer: 日本地球惑星科学連合 2015 年大会
  • Place of Presentation: 幕張メッセ国際会議場
  • Year and Date: 2015-05-22
• [Presentation] 高速に回転する薄い球殻内の熱対流により引き起こされる表層縞状構造の消滅 (2015)
  • Author(s): 佐々木洋平, 竹広真一, 石岡圭一, 中島健介, 林祥介
  • Organizer: 日本気象学会春季大会
  • Place of Presentation: 代々木オリンピックセンター
  • Year and Date: 2015-05-21
• [Presentation] 高速回転する薄い球殻中の対流により引き起こされる表層の帯状流 (2014)
  • Author(s): 佐々木洋平, 竹広真一, 石岡圭一, 中島健介, 林祥介
  • Organizer: 日本気象学会 2014 年度秋季大会
  • Place of Presentation: 福岡国際会議場
  • Year and Date: 2014-10-21 – 2014-10-23
• [Presentation] 高速回転する薄い球殻内の熱対流により引き起こされる表層の帯状流 (2014)
  • Author(s): 佐々木洋平, 竹広真一, 石岡圭一, 中島健介, 林祥介
  • Organizer: 2014 年日本流体力学会年会
  • Place of Presentation: 東北大学川内北キャンパス
  • Year and Date: 2014-09-15 – 2014-09-17
• [Presentation] Penetration of magneto-hydrodynamic disturbances into an outer strongly stable layer caused by MHD dynamo in a rotating spherical shell (2014)
  • Author(s): Sasaki,Y., Takehiro, S
  • Organizer: he 14th symposium of SEDI, Study of the Earth’s Deep Interior
  • Place of Presentation: the Shonan Village Center, Kanagawa, Japan,
  • Year and Date: 2014-08-03 – 2014-08-08
• [Presentation] 高速に回転する薄い球殻内の熱対流により引き起こされる表層の帯状流 (2014)
  • Author(s): 佐々木洋平, 竹広真一, 石岡圭一, 中島健介, 林祥介
  • Organizer: 日本地球惑星科学連合 2014 年大会
  • Place of Presentation: パシフィコ横浜
  • Year and Date: 2014-04-28 – 2014-05-02
• [Presentation] Diversity of atmospheric circulations of sycronized rotating Jovian type planets (2013)
  • Author(s): Takehiro, S., Sasaki, Y., Takahashi, Y. O., Nakajima, K., Hayashi, Y.-Y., Kuramoto, K.
  • Organizer: 5th Subaru International Conference: Exoplanets and Disks:Their Formation and Diversity II
  • Place of Presentation: Sheraton Kona Resort & Spa Keauhou Bay, The Big island of Hawaii.
  • Invited
• [Presentation] Weak-field dynamo emerging in a rotating spherical shell with stress-free top and no-slip bottom boundaries (2013)
  • Author(s): Sasaki, Y., Takehiro, S., Kuramoto, K., Hayashi, Y.-Y.
  • Organizer: Mathematical analysis of magneto-hydrodynamical processes in stars
  • Place of Presentation: Kansai Seminar House, Sakyo-ku, Kyoto, Japan.
• [Presentation] 回転球殻内の熱対流による角運動量輸送と太陽差分回転について (2013)
  • Author(s): 竹広真一, 佐々木洋平, 林祥介, 山田道夫
  • Organizer: 2013年日本流体力学会年会
  • Place of Presentation: 東京農工大学
• [Presentation] 回転球殻内の非弾性流体熱対流の線型安定性 (2013)
  • Author(s): 佐々木洋平, 竹広真一, 中島 健介, 林祥介
  • Organizer: 2013年日本流体力学会年会
  • Place of Presentation: 東京農工大学
• [Presentation] 恒星・ガス惑星・氷惑星内部を念頭においた非弾性球殻対流モデル (2013)
  • Author(s): 佐々木 洋平, 竹広 真一, 中島 健介, 林 祥介
  • Organizer: 日本地球惑星科学連合 2013 年大会
  • Place of Presentation: 幕張メッセ国際会議場