254 citations · 345 across the 9 of their papers we have counts for
9 papers
A Lagrange multiplier-based optimal control technique for streak attenuation in high-speed boundary layers
Omar Es-Sahli, Adrian Sescu, M. Z. A. Koshuriyan +2
High-amplitude free stream turbulence and surface roughness elements can excite a laminar boundary layer flow sufficiently to cause streamwise oriented vortices to develop. These v…
Investigation of Görtler vortices in high-speed boundary layers via an efficient numerical solution to the non-linear boundary region equations
Omar Es-Sahli, Adrian Sescu, Mohammed Afsar +1
Streamwise vortices and the associated streaks evolve in boundary layers over flat or concave surfaces due to disturbances initiated upstream or triggered by the wall surface. Foll…
Improving accuracy of turbulence models by neural network
Satoshi Miyazaki, Yuji Hattori
Neural networks of simple structures are used to construct a turbulence model for large-eddy simulation (LES). Data obtained by direct numerical simulation (DNS) of homogeneous iso…
Searching for turbulence models by artificial neural network
Masataka Gamahara, Yuji Hattori
Artificial neural network (ANN) is tested as a tool for finding a new subgrid model of the subgrid-scale (SGS) stress in large-eddy simulation. ANN is used to establish a functiona…
Explosive magnetic reconnection caused by an X-shaped current-vortex layer in a collisionless plasma
Makoto Hirota, Yuji Hattori, Philip J. Morrison
A mechanism for explosive magnetic reconnection is investigated by analyzing the nonlinear evolution of a collisionless tearing mode in a two-fluid model that includes the effects…
Variational Approach to Necessary and Sufficient Stability Conditions for Inviscid Shear Flow
Makoto Hirota, Philip J. Morrison, Yuji Hattori
A necessary and sufficient condition for linear stability of inviscid parallel shear flow is formulated by a novel variational method, where the velocity profile is assumed to be m…
New Approach for Error Reduction in the Volume Penalization Method
Wakana Iwakami, Yuzuru Yatagai, Nozomu Hatakeyama +1
A new approach for reducing error of the volume penalization method is proposed. The mask function is modified by shifting the interface between solid and fluid by (νη)^0.5 toward…
Reconnection and acoustic emission of quantized vortices in superfluid by the numerical analysis of the Gross-Pitaevskii equation
S. Ogawa, M. Tsubota, Y. Hattori
We study numerically the reconnection of quantized vortices and the concurrent acoustic emission by the analysis of the Gross-Pitaevskii equation. Two quantized vortices reconnect…
Large Coherent Structure Formation by Magnetic Stretching Term in Two-Dimensional MHD Turbulence
Akihiro Ishizawa, Yuji Hattori
Using EDQNM approximation, it is shown that the magnetic stretching term is responsible for turning the small-scale turbulent structures into the large coherent magnetic structures…