514 citations · 1.7k across the 51 of their papers we have counts for
7 papers · 1 filter
Lyapunov spectrum of separated flows and its dependence on numerical discretization
Pablo Fernandez, Qiqi Wang
We investigate the Lyapunov spectrum of separated flows and their dependence on the numerical discretization. The chaotic flow around the NACA 0012 airfoil at low Reynolds number a…
Toward real-time high-fidelity simulation using integral boundary layer modeling
Alexandre Marques, Qiqi Wang, Johan Larsson +2
One of the greatest challenges to using large-eddy simulations (LES) in engineering applications is the large number of grid points required near walls. To mitigate this issue, res…
Sensitivity analysis on chaotic dynamical system by Non-Intrusive Least Square Shadowing (NILSS)
Angxiu Ni, Qiqi Wang
This paper develops the non-intrusive formulation of the Least-squares shadowing (LSS) method, for computing the sensitivity of long-time averaged objectives in chaotic dynamical s…
Decomposition of stencil update formula into atomic stages
Qiqi Wang
In parallel solution of partial differential equations, a complex stencil update formula that accesses multiple layers of neighboring grid points sometimes must be decomposed into…
Adjoint-based Gradient Estimation Using the Space-time Solutions of Unknown Conservation Law Simulations
Han Chen, Qiqi Wang
Many control applications can be formulated as optimization constrained by conservation laws. Such optimization can be efficiently solved by gradient-based methods, where the gradi…
The swept rule for breaking the latency barrier in time advancing two-dimensional PDEs
Maitham Makki Alhubail, Qiqi Wang, John Williams
This article describes a method to accelerate parallel, explicit time integration of two-dimensional unsteady PDEs. The method is motivated by our observation that latency, not ban…
Simplified Least Squares Shadowing sensitivity analysis for chaotic ODEs and PDEs
Mario Chater, Angxiu Ni, Qiqi Wang
This paper develops a variant of the Least Squares Shadowing (LSS) method, which has successfully computed the derivative for several chaotic ODEs and PDEs. The development in this…