Inscrição na biblioteca: Guest
TSFP DL Home Arquivos Comitê executivo

DNS OF VELOCITY AND THERMAL FIELDS IN TURBULENT CHANNEL FLOW WITH TRANSVERSE-RIB ROUGHNESS

Yasutaka Nagano
Nagoya Industrial Science Research Institute; Department of Mechanical Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan

Hirofumi Hattori
Information and Analysis Technologies Division, Department of Mechanical Engineering, Nagoya Institute of Technology, Gokiso-cho, Showaku, Nagoya 466-8555, JAPAN

Shin-ya Yasui
Department of Mechanical Engineering, Nagoya Institute of Technology Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan

Tomoya Houra
Department of Electronical and Mechanical Engineering, Department of Environmental Technology, Nagoya Institute of Technology, Gokiso-cho, Showa-ки, Nagoya 466-8555, JAPAN

Resumo

A detailed knowledge of both velocity and thermal fields in wall turbulence disturbed by a row of ribs on the wall is important for clarifying the chief factors of fluid and thermal dynamics related to the control of heat transfer. In this study, in order to elucidate the effects of roughness on the statistical quantities in the velocity and thermal fields, direct numerical simulations (DNS) of heat transfer in turbulent channel flows with transverse-rib roughness are performed by varying their interval, width and height, in which the turbulent heat transfer with k-type and d-type roughness walls are simulated. It is found that since turbulent mixing is promoted by arranging ribs, the distributions of mean velocity and temperature become asymmetric markedly. And the systematic variations of secondary flow patterns between ribs are clearly identified. With the k-type roughness, the best heat transfer performance is found to be obtained.