pump piston powered boat

The boat which folds in two for transporting is in itself fairly unusual and we just wanted to have an unusual propulsion system.With this in mind I remembered that I was once stranded without a paddle in a small working boat, there was some 32mm diameter pipe in the boat and I used it to blow myself to the side by immersing the tube in the water at the back of the boat and just blowing. I was surprised how quickly the momentum built up. Having said all it looks like we would be better pumping water.

 

SamSam
The put put does not run on air but steam. The noise is a steam explosion that drives the water out of the tube.
TANSL:
No, you are getting it wrong. The propeller accelerates air and produces thrust. Constant speed = zero thrust.

 

Gonzo, sorry, I can not talk physics with you. I am not able to refute your arguments for though I know the basics of physics, I find it difficult to explain in terms understandable to you. The language, you know.
I do not speak of "F = m* a" but about "m * v", a physical quantity, I do not know how to name it in English.

 

I think the put put also sucks in water as some steam condenses, and then jets the water back out as some steam expands. Fun little toy. Light weight. Not efficient.

 

As for the piston air pump, just imagine yourself pumping on a foot pump or hand pump, even a bigger one for higher flow rate and lower pressure, and think about how effective it would be. Most of the energy would be dissipated as sound and heat in all directions. There is reason why flatulent swimmers don't win gold medals.

 

I would think a well rehearsed (anal aim reflex?) , overly flatulent swimmer would have ever so slightly better times.

 

TANSL:
F (force)= m(mass)*(multiplied by)a(acceleration) gives a measure of thrust
m(mass)*(multiplied by)v(velocity) gives a vector and the kinetic energy of a body.

 

No Gonzo, kinetice energy is m (mass) * (multiplied) V (velocity)^2 (second power).
m (mass) * (multiplied) v (velocity) never will be a vector.
You're confusing things for a physics student in the first quarter are already clear. I am sorry.

 

Velocity is a vector. Speed is not.

 

No, that's not right. But the question of which I speak is that you say "m * v gives a vector and the kinetic energy of a body." and that's a rookie mistake, m * v may not be the kinetic energy of any body.

 

momentum = mass x velocity

https://en.wikipedia.org/wiki/Momentum

kinetic energy = .5mv^2

https://en.wikipedia.org/wiki/Kinetic_energy

 

So in fact you have pushed some water from the tube with each breath.
Without the immersion you would have never reached the shore.

 

This thread proved yet another opportunity for gonzo and TANSL to strive for agreement about something. Anything ! The quest goes on.

 

.

Back in the day these bellows were used to power organs. this must have been for a very large one...



Maybe it could be converted for pumping water

 

pump piston powered boat Reply to Thread

Thanks for all your help and advice. I agree that it is better to pump water rather than air. I have attcched a sketch showing a two way cylinder pump. All advice very welcome and appreciated

Liam