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Author Topic: ultrasonic boat propulsion  (Read 3611 times)


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ultrasonic boat propulsion
« on: August 04, 2020, 12:46:46 PM »
two ultrasonic speakers against each other with phase difference propel the toy boat

i wonder if it would work better if they just pointed both of them backward

if it could be scaled up maybe it could replace propellers


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Re: ultrasonic boat propulsion
« Reply #1 on: August 07, 2020, 12:34:59 AM »
I have some ultrasonic water foggers that people use in a bowl with water and marbles and the fog comes out like a dry ice effect.

Maybe they can be used for the experiment if anyone wants to try. cheap on amazon or ebay, like 10 bucks. These are self contained circuit and the water level needs to be 1 to 3cm above the ceramic element, so that would have to be worked out. But, these things actually shoot the water in the air with the fog as if there were a small hose of water pressure just below the surface. Depending on the level above the element, the water can be splashy and get all over nearby things and table. So probably just one of these could drive the toy boat.

Have 4 of these things that were for another experiment that didnt pan out. If I have time this weekend ill do a short vid of the effects I have shared above and then try it as a propulsion of a simple boat.

Interesting.  Thanks



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Re: ultrasonic boat propulsion
« Reply #2 on: August 07, 2020, 07:28:28 PM »
This concept has been around since the early 1900's but never went mainstream. The problem was that in many peoples minds oscillating objects cannot produce a motive force because they move back and forth summing to zero not unlike Alternating Currents. However as we know they were wrong and the simple math they imagined in there head did not reflect reality.

Here we see oscillations producing pressure waves in the medium, corresponding regions higher and lower with respect to ambient not unlike a Sine Wave we see on our DSO. Now imagine a train with the box cars alternately labelled "high" and "low", if the train were stationary the wave would appear as something not unlike our sine wave where each individual car would alternate between high and low in a fixed position blinking like Christmas lights. While this can give the appearance of motion along a horizontal plane none is actually present, it's an illusion. However if our train was moving then each box car alternating between high and low is changing in it's condition and it's position. It is this change in position relative to ambient which allows it to interact with the ambient.

Here we have two basic options for interaction with ambient and the train can be moving or the high/low condition can move horizontally from one box car to the next. In some sense this was Einsteins problem concerning relativity and one could not tell whether the train was moving or the high/low wave was translating along a horizontal plane because they would appear to be identical to the observer. 

We could imagine a similar circumstance in an AC electrical system. The energy or phase differential is moving from source to sink along the conductor at a given velocity of X. However if the source, conductor and sink were moving through space at velocity X there would appear to be no observed phase differential, an illusion of sorts. 

What I find really interesting is that the only real requirements to produce a propulsive force is to produce a translating/moving wave which interacts with a given medium. The medium could be water, air or space and the only requirement is that the wave condition actually moves versus alternating states and also interacts with the medium. Almost anything is possible so long as these conditions are met in my opinion.



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Re: ultrasonic boat propulsion
« Reply #3 on: December 22, 2021, 03:21:47 PM »
I wonder how it will look in real conditions. The experiment with the boat model is certainly interesting, but have similar tests been carried out in practice? And what are the benefits of such boats? Who needs them? I really love yachts and boats. But I still prefer the classic versions of their technical equipment.  I accept experiments in design.  I am quite satisfied with the vessels rented from boat rentals miami in terms of their quality and appearance. Although I would be interested to see a boat with your installation in full size.