26 citations · 117 across the 12 of their papers we have counts for
12 papers
Optimal body force for heat transfer in turbulent vertical heated pipe flow
Shijun Chu, Elena Marensi, Ashley P. Willis
The vertical heated-pipe is widely used in thermal engineering applications, as buoyancy can help drive a flow, but several flow regimes are possible: shear-driven turbulence, lami…
Modelling the transition from shear-driven turbulence to convective turbulence in a vertical heated pipe
Shijun Chu, Elena Marensi, Ashley P. Willis
Heated pipe flow is widely used in thermal engineering applications, but the presence of buoyancy force can cause intermittency, or multiple flow states at the same parameter value…
Excitation and stability of nonlinear compressible Görtler vortices and streaks induced by free-stream vortical disturbances
Dongdong Xu, Pierre Ricco, Elena Marensi
We study the generation, nonlinear development and secondary instability of unsteady Görtler vortices and streaks in compressible boundary layers exposed to free-stream vortical di…
Laminarising turbulent pipe flow by linear and nonlinear optimisation
Shijun Chu, Ashley P. Willis, Elena Marensi
It has been observed that flattening the mean velocity profile of pipe flow by body force can laminarise turbulence, a promising means to reduce frictional drag substantially. To e…
The minimal seed for transition to convective turbulence in heated pipe flow
Shijun Chu, Ashley P. Willis, Elena Marensi
It is well known that buoyancy suppresses, and can even laminarise turbulence in upward heated pipe flow. Heat transfer seriously deteriorates in this case. Through a new DNS model…
Discontinuous transition to shear flow turbulence
Bowen Yang, Yi Zhuang, Gökhan Yalnız +3
Depending on the type of flow, the transition to turbulence can take one of two forms: either turbulence arises from a sequence of instabilities or from the spatial proliferation o…
Dynamics and proliferation of turbulent stripes in plane-Poiseuille and plane-Couette flows
Elena Marensi, Gökhan Yalnız, Björn Hof
The first long-lived turbulent structures observable in planar shear flows take the form of localized stripes, inclined with respect to the mean flow direction. The dynamics of the…
Symmetry-reduced Dynamic Mode Decomposition of Near-wall Turbulence
Elena Marensi, Gökhan Yalnız, Björn Hof +1
Data-driven dimensionality reduction methods such as proper orthogonal decomposition (POD) and dynamic mode decomposition (DMD) have proven to be useful for exploring complex pheno…
Suppression of turbulence and travelling waves in a vertical heated pipe
Elena Marensi, Shuisheng He, Ashley P. Willis
Turbulence in the flow of fluid through a pipe can be suppressed by buoyancy forces. As the suppression of turbulence leads to severe heat transfer deterioration, this is an import…
Designing a minimal baffle to destabilise turbulence in pipe flows
Elena Marensi, Zijing Ding, Ashley P. Willis +1
Motivated by the results of recent experiments (Kühnen et al., Flow Turb. Combust., vol. 100, 2018, pp. 919-943), we consider the problem of designing a baffle (an obstacle to the…
Upper edge of chaos and the energetics of transition in pipe flow
Nazmi Burak Budanur, Elena Marensi, Ashley P. Willis +1
In the past two decades, our understanding of the transition to turbulence in shear flows with linearly stable laminar solutions has greatly improved. Regarding the susceptibility…
Stabilisation and drag reduction of pipe flows by flattening the base profile
E. Marensi, A. P. Willis, R. R. Kerswell
Recent experimental observations (Kuehnen et al., 2018) have shown that flattening a turbulent streamwise velocity profile in pipe flow destabilises the turbulence so that the flow…