Turbulent mixing and cloud microphyscial processes by large scale parallel numerical computation

2014 Fiscal Year Final Research Report

• Project/Area Number: 24360068
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Fluid engineering
• Research Institution: Nagoya Institute of Technology
• Principal Investigator: GOTOH Toshiyuki 名古屋工業大学, 工学(系)研究科(研究院), 教授 (70162154)
• Co-Investigator(Kenkyū-buntansha): WATANABE Takeshi 名古屋工業大学, 大学院工学研究科, 准教授 (30345946) ; MIURA Hideaki 核融合科学研究所, ヘリカル研究部, 准教授 (40280599)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 乱流混合 / 雲マイクロ物理 / 大規模計算 / スカラー / 異常揺らぎ / 雲粒子

Outline of Final Research Achievements

Cloud microphysical simulator has been developed which computes growth of cloud droplets to rain drops udner the action of condensation, collision and turbulent mixing from the view point of the first principle. Evolution of cloud droplets and turbulence inside a parcel which is convected by the updraft has succesfully been computed for 20 minutes. Growth of mean droplet radius and expansion of the droplet spectrum are analized. The scaling exponents of the moments of passive scalar fluctuations in turbulence have been exmained by the large scale computation. It is found that the scaling exponents are not universal but those of the normalized moments are universal. Spectrum of the scalar fluctuations at very high Schmidt number such as aerosols which are essential to nucleation of cloud droplets has been examined. The spectrum is found to agree with the theoretical prediction and the effects of the velocity intermittency on the spectrum in the far diffusive range is also studied.

Free Research Field

流体工学