Abo Bibliothek: Guest
Home Archive Thermal Letter Beauftragte Zukünftige Meetings Assembly for International Heat Transfer Conferences
International Heat Transfer Conference 12

ISSN: 2377-424X (online)
ISSN: 2377-4371 (flashdrive)

DNS of the Scalar Transfer Across the Free-Surface in a Wind-Driven Turbulent Flow

Yoshinobu Yamamoto
Department of Nuclear Engineering, Kyoto University, Yoshida Sakyo-ku, Kyoto 606-8501,Japan

Tomoaki Kunugi
Department of Nuclear Engineering, Kyoto University, Kyoto Daigaku-Katsura, Nishikyo-ku, Kyoto, Japan

Akimi Serizawa
Department of Nuclear Engineering, Kyoto University, Yoshida-Honmachi, Kyoto 606-8501, Japan

DOI: 10.1615/IHTC12.470
6 pages

Abstrakt

In this study, Direct numerical simulation (DNS) of wind-driven turbulent flow at the Reynolds number is about 3300 based on the gas layer height and the free stream velocity, was conducted by the direct numerical solution procedure (MARS method) for a coupled gas-liquid flow. As the results, completely mass conservation was kept during the all calculation time and the capacity ofMARSmethod as themethod for DNS of multiphase turbulent flow was indicated. In wind-driven turbulent flow, local friction coefficient in gas sidewas 15% decreased comparedwith thewall turbulent flow. Near free surface, large horizontal scale shaped the water surface wave motion supplied the velocity fluctuations to the fluid motion. But, vertical component of turbulent intensity was constrained by the water surface existence as well as turbulent open-channel flow at low Froude number. In both gas- and water-side, high and low speed streaky structures were observed and these structures and surface wavemotion was interacted each other. It seems that relationships between wave height and turbulent boundary layer thickness was one of the important factors in wind-driven turbulent structure. In gas side, near air-liquid interface turbulent structures as well as the adverse and favorable pressure gradient flow caused from the wave motion, effect on the heat transfer near water surface. On the other hands, wave motion effect on the heat transfer across the air-liquid interface was relatively inactive, because of the thermal diffusivity difference between gas layer and water layer.

Kauf $25.00 Check subscription Ethik und Fehlverhalten bei Publikationen Meinem Bibliothekar empfehlen Lesezeichen auf dieser Seite setzen