Heat-transport scaling and transition in geostrophic rotating convection with varying aspect ratio

Lu, Hao-Yuan1; Ding, Guang-Yu2,3,4; Shi, Jun-Qiang1; Xia, Ke-Qing2,3,4; Zhong, Jin-Qiang1

2021-07-28

10.1103/PhysRevFluids.6.L071501

Physical Review Fluids   影响因子和分区

2469-990X

We present high-precision experimental and numerical studies of the Nusselt number Nu as functions of the Rayleigh number Ra in geostrophic rotating convection with the domain aspect ratio Gamma varying from 0.4 to 3.8 and the Ekman number Ek varying from 2.7x10(-5) to 2.0x10(-7). With decreasing Ra our heat-transport data Nu(Ra) reveal a gradual transition from buoyancy-dominated to geostrophic convection at large Ek, whereas the transition becomes sharp with decreasing Ek. We determine the power-law scaling of Nu similar to Ra-gamma, and find an unexpectedly strong Gamma dependence of the scaling exponent gamma. We further show that the boundary flows formed near the lateral wall give rise to pronounced enhancement of Nu over a broad range of the geostrophic regime, leading to reduction of gamma in small-Gamma cells. A very steep scaling with gamma > 3 is observed when the periodic lateral boundary condition is used, which manifests the significant differences between laterally confined and unconfined rotating thermal convection. The present work provides insight into the heat-transport scaling in geostrophic convection.

SCI ; EI

英语

通讯

National Science Foundation of China[11772235,12072144] ; NSFC/RGC Joint Research[1561161004,"N_CUHK437/15"] ; Hong Kong Research Grants Council[14302317]

Physics

Physics, Fluids & Plasmas

WOS:000679191500002

AMER PHYSICAL SOC

20213210748020

Aspect ratio

Heat Transfer:641.2

Web of Science

1.Tongji Univ, Sch Phys Sci & Engn, Shanghai 200092, Peoples R China
2.Southern Univ Sci & Technol, Ctr Complex Flows & Soft Matter Res, Shenzhen 518055, Peoples R China
3.Southern Univ Sci & Technol, Dept Mech & Aerosp Engn, Shenzhen 518055, Peoples R China
4.Chinese Univ Hong Kong, Dept Phys, Shatin, Hong Kong, Peoples R China

Lu, Hao-Yuan,Ding, Guang-Yu,Shi, Jun-Qiang,et al. Heat-transport scaling and transition in geostrophic rotating convection with varying aspect ratio[J]. Physical Review Fluids,2021,6(7).

Lu, Hao-Yuan,Ding, Guang-Yu,Shi, Jun-Qiang,Xia, Ke-Qing,&Zhong, Jin-Qiang.(2021).Heat-transport scaling and transition in geostrophic rotating convection with varying aspect ratio.Physical Review Fluids,6(7).

Lu, Hao-Yuan,et al."Heat-transport scaling and transition in geostrophic rotating convection with varying aspect ratio".Physical Review Fluids 6.7(2021).