Underwater Propulsion: Pumping Out Water for Acceleration

[RICKYtan]

Can water inside a submersible object be pumped outwards to provide an acceleration while underwater?

 

[Bystander]

Squid?

 

[fresh_42]

Can water inside a submersible object be pumped outwards to provide an acceleration while underwater?

Isn't this exactly what a propeller does? If you like, you can put the whole system in a tube through the inner of the object, but why?

 

[Nidum]

If you mean can water from a tank inside be pumped out to produce thrust then answer is yes but in practice this method of producing thrust is not very practical.

Generally better to use the water from lake or sea and pump it through or around the submersed object .

 

[davenn]

Generally better to use the water from lake or sea and pump it through or around the submersed object .

invented in my home country, the Hamilton Jet is the classic example of that
https://en.wikipedia.org/wiki/Jetboat

 

[fresh_42]

At least they are fast!
https://www.ngva.eu/worlds-fastest-high-speed-ferry-propelled-by-waertsilae-technology

 

[Nidum]

This is the UK version built by Dowty under license from Hamilton :

 

[Nidum]

Technical :

 

[RICKYtan]

Can someone explain how the intake works and the work necessary? Also, can intake be supplied by water flowing inside the system at a location on the system that is "in front of" the moving system, a system which can travel any direction underwater?

 

[Drakkith]

Can someone explain how the intake works and the work necessary?

The wikipedia article is a good starting point for an overview of a pump-jet: https://en.wikipedia.org/wiki/Pump-jet

If you're planning to build one then you'll have to get into the technical literature, as teaching you the details would be beyond the scope of this forum.

Also, can intake be supplied by water flowing inside the system at a location on the system that is "in front of" the moving system, a system which can travel any direction underwater?

I'm sorry but I can't make heads or tails of this.

 

[CWatters]

Perhaps Google Bow Thruster?

 

[sophiecentaur]

I visited the RNLI Lifeboat museum Pool, UK last year and saw an ancient (1950's?) lifeboat which used water jet propulsion. Nothing new under the Sun. Great for shallow water use.