A reduced-order model of three-dimensional unsteady flow in a cavity based on the resolvent operator

TL;DR

This paper introduces a new reduced-order modeling approach for 3D unsteady cavity flows using resolvent analysis, capturing complex vortex structures with low computational cost.

Contribution

It presents a novel resolvent-based reduced-order model that approximates nonlinear flow dynamics from limited data, improving efficiency and understanding of cavity flow phenomena.

Findings

Successfully models Taylor-Görler vortices with low-order resolvent decomposition

Provides velocity fluctuations from mean flow and single probe data

Demonstrates effectiveness in representing complex unsteady flow features

Abstract

A novel reduced-order model for nonlinear flows is presented. The model arises from a resolvent decomposition in which the nonlinear advection terms of the Navier-Stokes equation are considered as the input to a linear system in Fourier space. Results show that Taylor-G\"ortler-like vortices can be represented from a low-order resolvent decomposition of a nonlinear lid-driven cavity flow. The present approach provides an approximation of the fluctuating velocity given the time-mean and the time history of a single velocity probe.