There is a theme these days: one of Hamburg’s most famous sights, the concert hall called Elbphilharmonie. And not only is it a pretty impressive buildings, it’s located right at the port of Hamburg, and, more importantly, right across from my new work place! Yesterday morning there was a lot of ice on the puddle […]
From dawn til dusk (which wasn’t actually as long a time as it sounds ;-)), first day in my new job as programme manager of the citizen science project on biodiversity “GEO-Tag der Natur“. I am looking forward to great views on the way to and from work! And I am suuuper excited to be […]
Disclaimer: This post might well be called “fun with tides” similar to Sheldon Cooper’s “fun with flags” — it is super nerdy, but at least I am having fun! There is some really cool art around Hamburg, and the one I want to talk about today is called “four men on buoys” by Stephan Balkenhol: […]
You know I like to point out where you can spot hydrodynamics concepts in your everyday lives (at least if your everyday lives include strolls along rivers and generally a lot of water) A while back we went to Geesthacht. We were hoping for more ice on the Elbe river, but sadly there was none. […]
For most of my readers it might be pretty obvious what the movement of floating ice says about the flow field “below”, but most “normal” people would probably not even notice that there is something to see. So I want to present a couple of pictures and observations today to help you talk to the people around […]
Another early morning crossing this bridge. And the current and the sun glint were perfect for this kind of photos:They almost look like schlieren photography images in those super old papers, don’t they? And I find it extremely fascinating how you can see the boundary layer between the flow and the stagnant water, and how wind […]
I remember being on a looooong walk on some Danish dike when my sister was small and really didn’t want to walk any more, telling her about how phase velocity of shallow water waves depended on water depth and how you could observe that when waves are refracted towards the coast (assuming the sea floor has the […]
In the last post, I showed you flow separation on a pylon in Elbe river. Remember? Today, we are back at the same pylon, only that this time the tidal current is a lot less strong, but there is a lot of wind, so our focus is on wind-generated waves. It might be admittedly a […]
Or: fast inflow into nearly stagnant water body Did you ever notice how when certain ferries dock, they stop, already parallel to the dock, a couple of meters away from the dock and then just move sideways towards the dock? Usually they don’t even move passenger ferries any more, just use thrusters to keep them steady […]
Do you use a tide chart to find the best time for your Saturday walk, too? I showed you a vortex street on a plate formed by pulling a paint brush through sugary water as an example. Now today I want to show you the real thing: Instead of stagnant water and a moving object, I bring to […]
Kelvin-Helmholtz instabilities in a shear flow in Elbe river. Last week I talked about how I wanted to use the “Elbe” model in teaching. Here is another idea for an exercise: On the picture below you see Kelvin-Helmholtz instabilities. They might be kinda hard to make out from the picture, but there is a movie below where […]
