No it does not. I will suggest however that the relative performance would be similar whether the fin is moving through the water, or whether the 'hip' pivot joint is held stationary because you are still dealing with pressure gradients across the blade, and also the velocity of a diver moving through water is not that fast. Actually, when a diver is accelerating from a stop, the fin and diver is briefly not moving through the water at all, and so we would be mesasuring thrust when you start kicking while trying to build up velocity. One test I would like to set up is to move the guts of the machine onto a boat and repeat the tests on a lake, and then also you could obtain maximum boat speed. It really would not be that difficult to perform such a test, but you would want to use a relatively small boat of course.
Info What is the "best" fin?
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No it does not. I will suggest however that the relative performance would be similar whether the fin is moving through the water, or whether the 'hip' pivot joint is held stationary because you are still dealing with pressure gradients across the blade, and also the velocity of a diver moving through water is not that fast. Actually, when a diver is accelerating from a stop, the fin and diver is briefly not moving through the water at all, and so we would be mesasuring thrust when you start kicking while trying to build up velocity. One test I would like to set up is to move the guts of the machine onto a boat and repeat the tests on a lake, and then also you could obtain maximum boat speed. It really would not be that difficult to perform such a test, but you would want to use a relatively small boat of course.
You need to use a water tunnel for testing the fins with a given speed compared to steady water.
One such water tunnel is at the University of Genoa, where they test propellers or scale models of racing sail boats. The optimisation of fins is conceptually similar to the optimisation of a propeller, but there are many more variables to optimize, related to the variable geometry of the blade due to its flexibility and by the motion imposed to the fin by the human-variable biokinetic parameters related to leg geometry.
I am in contact with the researchers running the water tunnel at the University of Genoa, I even published a paper with them.
So if you are interested in experimenting your apparatus in their lab, I can place you in contact.
Here our paper: http://www.angelofarina.it/Public/Papers/291-ICSV25-2018.pdf
We work on the noise caused by the propellers.
Here a paper more focused on their cavitation water tunnel:
I'll keep that Genoa tunnel in mind, appreciate that.
Pretty interesting stuff you are working on. Speaking of a tunnel, makes me wonder if surrounding a ships propeller with a long sound insulated tunnel would quiet things down, but I guess there would be a reduction in efficiency in addition to practical issues. You probably don't have a lot of avenues to deal with that issue, one that comes to mind is perhaps doing something with leading edges or trailing edges of the propeller blade in hopes of mitigating sound,,, or better yet, simple,, just create some underwater sound cancelling technology, lol. Thanks Angelo.
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