107 citations · 318 across the 18 of their papers we have counts for
18 papers
Flow instability in Stokes layer of Carreau fluids
Mengqi Zhang, Dongdong Wan, Huanshu Tan
This study investigates the influence of shear-thinning on the instability of a prototype time-periodic flow, the Stokes layer, in Carreau fluids. The time-dependent base flow was…
On the intracyclic instability in Stokes layers
Mengqi Zhang
Time-dependent fluid dynamics plays a crucial role in both natural phenomena and industrial applications. Understanding the flow instabilities and transitions within these dynamica…
A Diffuse-Interface Marangoni Instability
Xiangwei Li, Dongdong Wan, Haohao Hao +3
We investigate a novel Marangoni-induced instability that arises exclusively in diffuse fluid interfaces, absent in classical sharp-interface models. Using a validated phase-field…
Reinforcement-learning-assisted control of four-roll mills: geometric symmetry and inertial effect
Xuan Dai, Da Xu, Mengqi Zhang +1
Embedding the intrinsic symmetry of a flow system in training its machine learning algorithms has become a significant trend in the recent surge of their application in fluid mecha…
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…
Marangoni Interfacial Instability Induced by Solute Transfer Across Liquid-Liquid Interfaces
Xiangwei Li, Dongdong Wan, Mengqi Zhang +1
This study presents analytical and numerical investigations of Marangoni interfacial instability in a two-liquid-layer system with constant solute transfer across the interface. Wh…
Numerical analyses of the flow past a short rotating cylinder
Yongliang Yang, Chenglei Wang, Rui Guo +1
This work studies the three-dimensional flow dynamics around a rotating circular cylinder of finite length, whose axis is positioned perpendicular to the streamwise direction. Dire…
Numerical analyses of wire-plate electrohydrodynamic flows
Xuerao He, Pedro A. Vázquez, Mengqi Zhang
We present numerical analyses of 2-D electrohydrodynamic (EHD) flows of a dielectric liquid between a wire electrode and two plate electrodes with a Poiseuille flow, using direct n…
Reinforcement-learning-based control of convectively-unstable flows
Da Xu, Mengqi Zhang
This work reports the application of a model-free deep-reinforcement-learning-based (DRL) flow control strategy to suppress perturbations evolving in the 1-D linearised Kuramoto-Si…
Moffatt eddies in electrohydrodynamic flows: numerical simulations and analyses
Xuerao He, Zhihao Sun, Mengqi Zhang
We study numerically a sequence of eddies in two-dimensional electrohydrodynamic (EHD) flows of a dielectric liquid, driven by an electric potential difference between a hyperbolic…
On the large-Weissenberg-number scaling laws in viscoelastic pipe flows
Dongdong Wan, Ming Dong, Mengqi Zhang
This work explains a scaling law of the first Landau coefficient of the derived Ginzburg-Landau equation (GLE) in the weakly nonlinear analysis of axisymmetric viscoelastic pipe fl…
Numerical Study of Viscoelastic Upstream Instability
Sai Peng, Tingting Tang, Jianhui Li +2
In this work, we report numerical results on the flow instability and bifurcation of a viscoelastic fluid in the upstream region of a confined cylinder in a narrow channel. Two-dim…
Nonlinear spatiotemporal instabilities in two-dimensional electroconvective flows
Zhe Feng, Dongdong Wan, Bo-Fu Wang +1
This work studies the effects of a through-flow on two-dimensional electrohydrodynamic (EHD) flows of a dielectric liquid confined between two plane plates, as a model problem to f…
Reinforcement-learning-based control of confined cylinder wakes with stability analyses
Jichao Li, Mengqi Zhang
This work studies the application of a reinforcement-learning-based (RL) flow control strategy to the flow past a cylinder confined between two walls in order to suppress vortex sh…
Onset of vortex shedding around a short cylinder
Yongliang Yang, Zhe Feng, Mengqi Zhang
This paper presents results of three-dimensional direct numerical simulations (DNS) and global linear stability analyses (LSA) of a viscous incompressible flow past a finite-length…
Subcritical and supercritical bifurcations in axisymmetric viscoelastic pipe flows
Dongdong Wan, Guangrui Sun, Mengqi Zhang
Axisymmetric viscoelastic pipe flow of Oldroyd-B fluids has been recently found to be linearly unstable by Garg et al. Phys. Rev. Lett., 121.024502 (2018). From a nonlinear point o…
Modal and nonmodal stability analysis of electrohydrodynamic flow with and without cross-flow
Mengqi Zhang, Fulvio Martinelli, Jian Wu +2
We report the results of a complete modal and nonmodal linear stability analysis of the electrohydrodynamic flow (EHD) for the problem of electroconvection in the strong injection…