Open source codes

FreeFem++ code for computing effective boundary conditions at porous free-flow interface

This software is a script compilation for FreeFem++ to solve interface cell problems and arrive with coefficients in boundary condition (BC) between porous medium and free fluid. The MSE_bc software is licensed under LGPLv3 license.

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Fluid-Structure interaction (Navier-Stokes) solver

This is a simple tool for solving fluid-structure interaction problems. The flow solver based 2nd-order finite volume method on a staggered grid.  The approach for modeling rigid and fixed boundaries is based on the immersed boundary projection method and the approach for handling the two-way coupling between fluids and flexible structures is based on the penalty immersed boundary method. The code is available in both C and Matlab. Send me an email if your are interested in a copy.

Solver for Kuramuto Sivashinsky equation

A suite of scripts for the active control of the linerized Kuramuto-Sivashinsky equation, which is a good model for Tollmien-Schlichting waves in flat-plate boundary layer. Both model-based (LQG, MPC) and model-free (LMS, X-filtered LMS) methods are applied and compared. Written by Nicolo Fabbiane.

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Matlab code for Ginzburg-Landau equation

A suite of scripts for the stability analysis and control design applied to a model of spatially developing flows. The scripts reproduce the figures in following article.

The Matlab scripts compute the following for the complex Ginzburg-Landau equation: Neutral stability curves, perturbation in globally unstable flow, linear transient growth, global, POD and balanced modes, optimal disturbance and optimal energy growth, global spectrum and the pseudospectrum, input-output behavior: evolution in space and time of the state and time signals when forced by random noise, response to impulsive input, Input-output pseudospectra and frequency response, response to stochastic forcing, Controllability and observability gramians, spatial support of leading global, POD and balanced modes, actuator and sensor placement for the supercritical configuration, impulse response, perturbation energy and spectrum of the uncontrolled system and LQG-controlled system, model reduction error of the POD, balanced and global modes, frequency response of reduced-models, HSV of exact and snapshot-based balanced truncation, mean of the error covariance from solving the Riccati-equation compared to estimation error from the estimator, the rms-value of the error and the state, controlled Ginzburg-Landau equation with stochastic excitation, comparison of the frequency response of the open-loop with LQG and Hinfty approach

Download here.