Recent article in J. Magnet. Reson. (i guess it is magnetic resonance) reports on 1 meter-per-second flow, measured with some special trick and NMR. That's what we call "serious" competition.
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Biplab Das's blog reports about Smart-PIV project:
A New Technique To Improve Heart Implants’ Design
A technology used to measure airflow over wings can now be used to keep ailing hearts in good shape. Known as Particle Image Velocimetry (PIV) system, the technology has been optimised in a way that it could accurately measure the effects of medical implants on blood flow. This new avatar of PIV will help medical device manufacturers to improve the design of artificial implanted devices like heart valves and pumps. At the same time, it will be an indispensable tool for doctors to pin down and correct side-effects that affect patients having such implants.
read more on the original blog >>>
cross post from the dubious quality blog
Hummingbird Flight
There's a fascinating article over at the National Science Foundation about how hummingbirds fly. Here's an excerpt on their methodology:
In this study, the researchers applied "digital particle imaging velocimetry" (DPIV) to follow the flapping wings. DPIV is used in various applications to study flow characteristics of liquids and gases. By taking pictures with a special computer-coupled camera lighted with a laser, the distance traveled by individual particles seeded in a liquid or gas can be tracked through successive images. Hence, DPIV allows the researchers to follow the particles' movement image by image, like looking through the pages of a high-tech flipbook.
To observe the hummingbird in flight, the air in a wind tunnel was seeded with microscopic particles of olive oil, and digital images were captured every 300 microseconds as the bird hovered at a feeder. The wing beats caused the air to circulate, which in turn caused the floating oil particles to move. Computer-aided image analysis of each oil particle's position in consecutive frames allowed the scientists to reconstruct the lift and characteristics associated with each up and down wing movement.
So I feel really stupid now, which is fortunately kind of a hobby of mine.
Here's the link:
http://www.nsf.gov/news/news_summ.jsp?cntn_id=104263&org=NSF.
And this image is from another blog (Invisible Cinema) about the same work. This time it's a real data:
The Insitute of Environmental Engineering (IFU) and Institute of Geodesy and Photogrammetry (IGP) at the ETH Zurich opens the source of the three-dimensional Particle Tracking Velocimetry (3D-PTV) software for academic use. Everyone can request it by sending an e-mail. URAPIV greets every open science project and especially open source ones. In addition, Alex has opened a Wiki for all PTV users that it is edited collaboratively to promote the code and improve it's documentation. Wiki will have also some more codes for the post-processing, turbulent flow analysis, etc., written for years in C, C++, Matlab. Wiki looks nice and we consider to move URAPIV there too :-). It will allow all our users to edit it's documentation, which is still missing - sorry for that.
Alex just found that in 1932, A. Fage and H.C.H. Townend published an article in Proceedings of the Royal Society of London (Series A), vol. 135, No. 828, pp. 656-677, which is: "An Examination of Turbulent Flow with an Ultramicroscope".
Are you kidding me :-)?
And were waiting until 1998 to reinvent it as microPIV?
Look at the sketch and tell me if they didn't do also Nano-PIV?
The full article is available through JSTOR: http://www.jstor.org
We are not sure if we are allowed to show here the copy of the figures which are most probably copyrighted, but it is so striking when we see such a thing and it's impossible to express it otherwise. We argue not to copy this images and purchase the original article from JSTOR. We add the copyright notice as it is provided by JSTOR:
A simple but groundbreaking experiment performed more than 70 years ago finally has been explained by scientists at the University of Illinois at Urbana-Champaign. The solution sheds new light on fluid turbulence — the last major unsolved problem in classical physics.
"Turbulence is the jittery, swirling behavior of a gas or liquid when flowing next to a wall or around an obstacle," said Gustavo Gioia, a professor of theoretical and applied mechanics at Illinois. "Although most of the flows that surround us in everyday life are turbulent flows over rough walls, these flows have remained one of the least understood phenomena of classical physics."
http://www.whatsnextnetwork.com/technology/htsrv/trackback.php/1639
There are two main sources of information for our users that want to join us in the move from (we stress out that the move is not complete move, we keep URAPIV development and support) URAPIV to PyPIV, or in more general sense, from Matlab to Python.
Very useful set of commands in PDF format by Johnvey Hwang, aka 37 mm website - see the blog here or press on the [link] to download the PDF.
A new Wiki, called NumPy for Matlab Addicts (that we fell like ones). NumPy is a package we use for PyPIV
I want to break free …. (Queen)
URAPIV wants to break free … (of Mathworks licensing policy) 
URAPIV now is also*
PyPIV, where Py is for Python (http://www.python.org)
* means that we are not going to drop the Matlab toolbox, but in parallel we are going to enter a new field: ABSOLUTELY FREE OPEN SOURCE PIV ANALYSIS (as they say think of "free as beer"). Even kids in a primary school in Gana can do PIV now - it's free as Python programming language is free, it's free as Python Imaging Library is free, it's free as Scientific Python is free.
If you install totally free OS for human beings - Ubuntu (or any other Linux distribution), you have Python built-in
If you have Windows, download an excellent distribution from Enthought Inc. and run the Windows installer. You'll have Python working in a minute.
If you're in Mac OS X, we still have not tested it, but MacPython is there and Fink is there, so it should be straightforward installation.
Happy PIVing to all
Here's a screenshot of PyPIV on a PC with Windows XP and Enthough Python at the background:
If you open Physics Today, December 2005 issue, you’ll find out an excellent artcile about Ludwig Prandtl’s Boundary Layer theory by John D Anderson Jr. Turbulent Boundary Layer is our “favorite” turbulent flow (see below the work we’ve done in the turbulent boundary layer flows, or follow the links to the authors, Uri, Roi or Alex)
We are proud to be a humble member of the experimental fluid mechanics community, working both in Physics and Engineering areas.
For those who cannot afford to subscribe for this journal or those who’s in engineering and never read this magazine, i made an unprofessional, ugly scan of the article. Please, use it only for the personal reading and do not distribute it. All the rights are reserved to Physics Today.
