TY - CONF
T1 - GROWING TURBULENT SPOT IN PLANE COUETTE FLOW PROVIDES DISSIMILARITY BETWEEN MOMENTUM AND HEAT TRANSFERS
AU - Fukudome, Koji
AU - Tsukahara, Takahiro
AU - Mamori, Hiroya
AU - Yamamoto, Makoto
N1 - Funding Information:
K.F. acknowledges the support of the Grant-in-Aid for Early-Career Scientists (No. 20K14671), and T.T. acknowledges the supports of the Grant-in-Aid for Scientific Research (B) (No. 19H02071) by Ministry of Education, Culture, Sports, Science and Technology of Japan.
Publisher Copyright:
© 2022 12th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2022. All rights reserved.
PY - 2022
Y1 - 2022
N2 - Direct numerical simulation of a turbulent spot developing in a laminar plane Couette flow was performed to study the dissimilarity between the heat and momentum transfers. The seed of the turbulent spot was a vortex pair, and the initial flow had an absolute similarity state between heat and momentum transfers. The turbulent spot grows gradually in the early stage and rapidly in the latter stage. The effective heat transfer state, which achieves larger heat transfer than momentum transport, was confirmed in the rapidly developing process. The dissimilarity mechanism was investigated by using a FIK identity equation. We clarified that the turbulent contributions in the friction coefficient and the Stanton number provided the effective heat transfer state. The budgets of Reynolds shear stress and heat flux exhibited that the dissimilarity was attributed to the differences in the pressure-strain and dissipation terms, and the difference in the production terms leads to adverse effects on the effective heat transfer. After the developing process, the pressure-strain term causes a decrease of the heat transfer compared to the skin friction.
AB - Direct numerical simulation of a turbulent spot developing in a laminar plane Couette flow was performed to study the dissimilarity between the heat and momentum transfers. The seed of the turbulent spot was a vortex pair, and the initial flow had an absolute similarity state between heat and momentum transfers. The turbulent spot grows gradually in the early stage and rapidly in the latter stage. The effective heat transfer state, which achieves larger heat transfer than momentum transport, was confirmed in the rapidly developing process. The dissimilarity mechanism was investigated by using a FIK identity equation. We clarified that the turbulent contributions in the friction coefficient and the Stanton number provided the effective heat transfer state. The budgets of Reynolds shear stress and heat flux exhibited that the dissimilarity was attributed to the differences in the pressure-strain and dissipation terms, and the difference in the production terms leads to adverse effects on the effective heat transfer. After the developing process, the pressure-strain term causes a decrease of the heat transfer compared to the skin friction.
UR - http://www.scopus.com/inward/record.url?scp=85143830417&partnerID=8YFLogxK
M3 - Paper
AN - SCOPUS:85143830417
T2 - 12th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2022
Y2 - 19 July 2022 through 22 July 2022
ER -