153 citations · 1.3k across the 35 of their papers we have counts for
31 papers · 1 filter
Universal transport laws in buoyancy-driven porous mixing
Marco De Paoli, Xiaojue Zhu
Buoyancy-driven convection in porous media governs heat and mass transport in a wide range of natural and engineered systems, from groundwater aquifers and geothermal reservoirs to…
Flapping dynamics of a compliant membrane in a uniform incoming flow
Chengyao Zhang, Ankang Gao, Xiaojue Zhu
Recent theoretical and experimental investigations have revealed that flapping compliant membrane wings can significantly enhance propulsive performance (e.g. Tzezana and Breuer, 2…
Vortex-magnetic competition and regime transitions in antiparallel flux tubes
Weiyu Shen, Rodolfo Ostilla-Mónico, Xiaojue Zhu
Vortex-magnetic interactions shape magnetohydrodynamic (MHD) turbulence, influencing energy transfer in astrophysical, geophysical, and industrial systems. On the Sun, granular-sca…
Reinforcement-learning-based control of turbulent channel flows at high Reynolds numbers
Zisong Zhou, Mengqi Zhang, Xiaojue Zhu
Deep reinforcement learning (DRL) is employed to develop control strategies for drag reduction in direct numerical simulations (DNS) of turbulent channel flows at high Reynolds num…
Linear instability in thermally-stratified quasi-Keplerian flows
Dongdong Wan, Rikhi Bose, Mengqi Zhang +1
Quasi-Keplerian flow, a special regime of Taylor-Couette co-rotating flow, is of great astrophysical interest for studying angular momentum transport in accretion disks. The well-k…
Transport scaling in porous media convection
Xiaojue Zhu, Yifeng Fu, Marco De Paoli
We present a theory to describe the Nusselt number (), corresponding to the heat or mass flux, as a function of the Rayleigh--Darcy number (), the ratio of buoyant driving…
Threshold Current Density for Diffusion-controlled Stability of Electrolytic Surface Nanobubbles
Yixin Zhang, Xiaojue Zhu, Jeffery A. Wood +1
Understanding the stability mechanism of surface micro/nanobubbles adhered to gas-evolving electrodes is essential for improving the efficiency of water electrolysis, which is know…
Scaling relations in quasi-static magnetoconvection with a strong vertical magnetic field
Shujaut H. Bader, Xiaojue Zhu
The scaling law for the horizontal length scale relative to the domain height , originating from the linear theory of quasi-static magnetoconvection, $\ell/L \sim Q^{-1/6…
Scaling regimes in rapidly rotating thermal convection at extreme Rayleigh numbers
Jiaxing Song, Olga Shishkina, Xiaojue Zhu
The geostrophic turbulence in rapidly rotating thermal convection exhibits characteristics shared by many highly turbulent geophysical and astrophysical flows. In this regime, the…
Predicting unavailable parameters from existing velocity fields of turbulent flows using a GAN-based model
Linqi Yu, Mustafa Z. Yousif, Young-Woo Lee +4
In this study, an efficient deep-learning model is developed to predict unavailable parameters, e.g., streamwise velocity, temperature, and pressure from available velocity compone…
Effects of radius ratio on annular centrifugal Rayleigh-Bénard convection
Dongpu Wang, Hechuan Jiang, Shuang Liu +2
We report on a three-dimensional direct numerical simulation study of flow structure and heat transport in the annular centrifugal Rayleigh-Bénard convection (ACRBC) system, with c…
Closing the loop: nonlinear Taylor vortex flow through the lens of resolvent analysis
Benedikt Barthel, Xiaojue Zhu, Beverley J. McKeon
We present an optimization-based method to efficiently calculate accurate nonlinear models of Taylor vortex flow. We use the resolvent formulation of McKeon & Sharma (2010) to mode…
Supergravitational turbulent thermal convection
Hechuan Jiang, Xiaojue Zhu, Dongpu Wang +2
High-Rayleigh number convective turbulence is ubiquitous in many natural phenomena and in industries, such as atmospheric circulations, oceanic flows, flows in the fluid core of pl…
From Rayleigh-Bénard convection to porous-media convection: how porosity affects heat transfer and flow structure
Shuang Liu, Linfeng Jiang, Kai Leong Chong +6
We perform a numerical study of the heat transfer and flow structure of Rayleigh-Bénard (RB) convection in (in most cases regular) porous media, which are comprised of circular, so…
Diffusive interaction of multiple surface nanobubbles and nanodroplets: shrinkage, growth, and coarsening
Xiaojue Zhu, Roberto Verzicco, Xuehua Zhang +1
Surface nanobubbles are nanoscopic spherical-cap shaped gaseous domains on immersed substrates which are stable, even for days. After the stability of a {\it single} surface nanobu…
Reply to "Absence of Evidence for the Ultimate Regime in Two-Dimensional Rayleigh-Bénard Convection"
Xiaojue Zhu, Varghese Mathai, Richard J. A. M. Stevens +2
Rely to the comment by Doering et al. in Phys. Rev. Lett. 123, 259401 (2019)
Flow organization and heat transfer in turbulent wall sheared thermal convection
Alexander Blass, Xiaojue Zhu, Roberto Verzicco +2
We perform direct numerical simulations of wall sheared Rayleigh-Bénard (RB) convection for Rayleigh numbers up to , Prandtl number unity, and wall shear Reynolds numbers…
Direct numerical simulations of Taylor--Couette turbulence: the effect of sand grain roughness
Pieter Berghout, Xiaojue Zhu, Daniel Chung +3
Progress in roughness research, mapping any given roughness geometry to its fluid dynamic behaviour, has been hampered by the lack of accurate and direct measurements of skin-frict…
Rough wall turbulent Taylor-Couette flow: the effect of the rib height
Ruben A. Verschoof, Xiaojue Zhu, Dennis Bakhuis +4
In this study, we combine experiments and direct numerical simulations to investigate the effects of the height of transverse ribs at the walls on both global and local flow proper…
Transition to ultimate Rayleigh-Bénard turbulence revealed through extended self similarity scaling analysis of the temperature structure functions
Dominik Krug, Xiaojue Zhu, Daniel Chung +3
In turbulent Rayleigh-Bénard (RB) convection, a transition to the so-called ultimate regime, in which the boundary layers (BL) are of turbulent type, has been postulated. Indeed, a…
Transition to the ultimate regime in two-dimensional Rayleigh-Bénard convection
Xiaojue Zhu, Varghese Mathai, Richard J. A. M. Stevens +2
The possible transition to the so-called ultimate regime, wherein both the bulk and the boundary layers are turbulent, has been an outstanding issue in thermal convection, since th…
Turbulent thermal superstructures in Rayleigh-Bénard convection
Richard J. A. M. Stevens, Alexander Blass, Xiaojue Zhu +2
We report the observation of superstructures, i.e.\ very large-scale and long living coherent structures in highly turbulent Rayleigh-Bénard convection up to Rayleigh . We…
Experimental investigation of heat transport in homogeneous bubbly flow
Biljana Gvozdic, Elise Almeras, Varghese Mathai +6
We present results on the global and local characterisation of heat transport in homogeneous bubbly flow. Experimental measurements were performed with and without the injection of…
Wall roughness induces asymptotic ultimate turbulence
Xiaojue Zhu, Ruben A. Verschoof, Dennis Bakhuis +4
Turbulence is omnipresent in Nature and technology, governing the transport of heat, mass, and momentum on multiple scales. For real-world applications of wall-bounded turbulence,…