Navier-Stokes solvers are complicated programs. Using them properly requires knowledge and skills. Also, the user has to prepare the input to the solver, that is, first and foremost, the geometry of the boundaries of the flow. In many cases this task is done using additional specialised software.
What, however, if all one wants is just a movie of the flow, and all one has as an input is the picture of the body, the flow past which needs to be visualised? Flow Illustrator is the answer to this. Its first version, an online server, allows the user to upload the picture, adjust a few parameters if desired, and receive a movie of the flow past it. Figures 1, 2, and 3 illustrate the sequence.
Fig.1. Draw a picture in Paint and save it.
Fig.2. Click on the figure, which is a link to the Flow Illustrator server. Proceed to "Try it" section. Upload your file, adjust parameters, and run the calculation.
Fig.3. Once ready, download the movie and watch it.
This project is a mixture of entertainment, education, public engagement, and research into human-computer interaction.
. For teaching purposes a stand-alone version, an Interactive Flow Illustrator, was developed in 2011-2012
under the Imperial College London Faculty of Engineering-Enabled
Project Interactive Flow Illustrator
(Principal Investigators Profs.S.Chernyshenko and S. Eisenbach).
Fig.4. Interactive Flow Illustrator.
Interactive Flow Illustrator works on the computer of the user and shows the flow visualisation in real time on the screen rather than recording a movie. The Reynolds number and the movie speed can be adjusted on the go. Attempts were also made of using a video camera as a source of the input image in real time. In the future the technology of using images as the input format might find other applications.
Further information:
Try it, it is easy and it is fun!
Studying fluid flows with auxiliary functions and LMIsat the IFAC World Congress, held in Yokohama, Japan on 8-14th July 2023.
Bounding time averages: a road to solving the problem of turbulenceat Institut de Mathématiques de Bordeaux, Bordeaux, May 4, 2023.
Bounding time averagesand
How quasi-steady is the modulation of near-wall turbulence by large-scale structures?(with Yunjiu Yang).
Auxiliary functionals: a path to solving the problem of turbulenceat The Seminar in the Analysis and Methods of PDE (SIAM PDE) on March 4, 2021. Links to the abstract and the video.
Accelerating time averagingat 73rd Annual Meeting of the APS Division of Fluid Dynamics, November 22, 2020: abstract and video.
Accelerating time averaging using auxiliary functionsat the Aerodynamics and Flight Mechanics group seminar, University of Southampton, on 6 February 2019
Coherent structures in wall-bounded turbulence: new directions in a classic problem, London, August 29-31, 2018, with a talk
Large-scale motions for the QSQH theory(with Chi Zhang).
Questions concerning quasi-steady mechanism of the Reynolds number, pressure gradient, and geometry effect on drag reductionat the Workshop on Active Drag Reduction, Aachen, Germany, 15-16 March 2018.
The problem of turbulence: bounding solutions to equations of fluid mechanics & other dynamical systems, with Giovanni Fantuzzi providing exercise sessions, at The 6th Bremen Winter School
Dynamical systems and turbulence, March 12-16, 2018.
Sergei Chernyshenko