Propulsion system

A propulsion system comprising a flow passage having an intake for communicating with a source of working liquid and an outlet, a mixing zone disposed within the flow passage between the intake and outlet, aeration means for aerating the working liquid with an aerating gas before delivery thereof to the mixing chamber, and a nozzle means for introducing a jet of hot compressible driving fluid into the mixing zone in a flow direction towards the outlet whereby a three-phase fluid regime is created in the mixing zone by virtue of the interaction of the aerating gas, the working liquid and the driving fluid, and whereby interaction between the driving fluid and the working liquid in the mixing zone develops a pressure reduction relative to the intake pressure to cause working liquid to be drawn from said source into the mixing zone and propelled towards the outlet.

A propulsion system comprising a flow passage having an intake for communicating with a source of working fluid and an outlet, a mixing zone disposed within the flow passage between the intake and outlet, and a nozzle means for injecting a condensable vapour into the nixing zone in a flow direction towards the outlet, whereby interaction between the condensable vapour and the working liquid in the mixing zone causes the vapour to condense providing a volume reduction to create a suction effect to cause working liquid to be drawn from said source into the mixing zone and propelled towards the outlet, and means for aerating the working fluid with an aerating gas prior to interaction of the driving fluid in the mixing zone whereby a three-phase fluid regime is created in the mixing zone by virtue of the interaction of the aerating gas, the working fluid and the condensable vapour.

A propulsion system for a watercraft accommodated on or in a body of water, the propulsion system comprising a flow passage having an intake for communicating with the body of water and an outlet, a mixing zone disposed within the flow passage between the intake and outlet whereby a stream of water drawn from the body of water through the intake as a working fluid can enter the mixing zone, and an injection means for injecting a hot compressible driving fluid into the mixing zone in a flow direction towards the outlet, whereby interaction between the driving fluid and the water in the mixing zone develops a zone of reduced pressure to cause a stream of water to be drawn from the body of water into the mixing zone and propelled towards the outlet, and means for aerating the water with an aerating gas prior to interaction of the driving fluid in the mixing zone whereby a three-phase fluid regime is created in the mixing zone by virtue of the interaction of the aerating gas, the water and the driving fluid.

A propulsion system for a watercraft accommodated on or in a body of water, the propulsion system comprising a flow passage having an intake for communicating with the body of water and an outlet, a mixing zone disposed within the flow passage between the intake and outlet whereby a stream of water drawn from the body of water through the intake can enter the mixing zone, and for introducing a hot compressible driving fluid into the mixing zone, whereby interaction between the driving fluid and the water in the mixing zone develops a zone of reduced pressure to cause a stream of water to be drawn from the body of water into the mixing zone and propelled towards the outlet, and means for aerating the working fluid with an aerating gas prior to interaction of the driving fluid in the mixing zone whereby a three-phase fluid regime is created in the mixing zone by virtue of the interaction of the aerating gas, the water and the driving fluid, the propulsion system being devoid of an impeller or other mechanical device for generating fluid flow along the flow passage to provide thrust at the outlet.

A drive system for a watercraft adapted to be accommodated on or in a body of water, the drive system comprising a steam generator for generating a supply of steam, and a propulsion system, the propulsion system comprising a flow passage having an intake for communicating with the body of water and an outlet, a mixing zone disposed within the flow passage between the intake and the outlet whereby a stream of water drawn from the body of water through the intake can enter the mixing zone, and an injection means for injecting steam generated by the steam generator into the mixing zone in a flow direction towards the outlet, whereby interaction between the steam and the water in the mixing zone causes water to be drawn from the body of water into the mixing zone and propelled towards the outlet, and means for aerating the water with an aerating gas prior to interaction of the steam in the mixing zone whereby a three-phase fluid regime is created in the mixing zone by virtue of the interaction of the aerating gas, the water and the steam.

A method of generating a fluid flow comprising the steps of:

• providing a flow passage having an intake and an outlet, locating the intake of the flow passage to communicate with a source of primary fluid from which the fluid flow is to be established;
• and introducing a driving fluid into the flow passage for interacting with primary fluid in the flow passage to develop a pressure reduction at a zone in the flow passage to cause primary fluid to be drawn from said source into said zone and propelled towards the outlet;
• and further comprising the step of aerating the primary fluid with an aerating gas prior to the introduction of the driving fluid into the primary fluid whereby a three-phase fluid regime is created in the flow passage by virtue of the interaction of the aerating gas, the primary fluid and the driving fluid.

A method of propelling a watercraft through a body of water, the method comprising the steps of:

• providing the watercraft with a flow passage having an intake and an outlet both opening onto the body of water;
• and introducing a driving fluid into the flow passage to develop a pressure reduction at a zone in the flow passage to cause water from the body of water to be drawn through the inlet into said zone and propelled towards the outlet as a stream for propelling the watercraft;
• and further comprising the step of aerating the water with an aerating gas prior to the introduction of the driving fluid into the water whereby a three-phase fluid regime is created in the flow passage by virtue of the interaction of the aerating gas, the water and the driving fluid.

A method of propelling a watercraft through a body of water, the method comprising the steps of:

• providing the watercraft with a flow passage having an intake and an outlet both opening onto the body of water;
• and introducing a condensable vapour such as steam into the flow passage to provide a volume reduction upon condensation of the vapour and thereby create a suction effect at a zone in the flow passage to cause water from the body of water to be drawn through the inlet into said zone and propelled towards the outlet as a stream for propelling the watercraft;
• and further comprising the step of aerating the water with an aerating gas prior to the introduction of the condensable vapour into the water whereby a three-phase fluid regime is created in the flow passage by virtue of the interaction of the aerating gas, the water and the condensable vapour.

A propulsion system comprising a flow passage having an intake for communication with a source of working fluid and an outlet, a mixing zone disposed within the fluid passage between the intake and the outlet, a nozzle means for introducing a jet of driving fluid into the mixing zone in a flow direction towards the outlet, whereby interaction between the driving fluid and the working fluid in the mixing zone causes working fluid to be drawn from the source into the mixing zone and propelled towards the outlet, the nozzle means having a nozzle passage of selectively variable size, and means for aerating the working fluid with an aerating gas prior to interaction of the driving fluid in the mixing zone whereby a three-phase fluid regime is created in the mixing zone by virtue of the interaction of the aerating gas, the working fluid and the driving fluid.

A drive system for a watercraft adapted to be accommodated on or in a body of water, the propulsion system comprising a flow passage having an intake for communicating with the body of water and an outlet, a mixing zone disposed within the flow passage between the intake and the outlet whereby a stream of water drawn from the body of water through the intake can enter the mixing zone, and a nozzle means for introducing a jet of driving fluid into the mixing zone in the flow direction towards the outlet, whereby interaction between the driving fluid and water causes water to be drawn through the intake from the body of water and propelled towards the outlet, the nozzle means having a nozzle passage of selectively variable size, and means for aerating the working fluid with an aerating gas prior to interaction of the driving fluid in the mixing zone whereby a three-phase fluid regime is created in the mixing zone by virtue of the interaction of the aerating gas, the water and the driving fluid.

A drive system for a watercraft adapted to be accommodated on or in a body of water, the drive system comprising a steam generator for generating a supply steam, a propulsion system comprising a flow passage having an intake for communication with the body of water and an outlet, a mixing zone disposed within the flow passage between the intake and outlet whereby a stream of water drawn from the body of water through the intake can enter the mixing zone, and a steam nozzle means for introducing steam into the mixing zone in a flow direction towards the outlet, whereby interaction between the steam and the water causes water to be drawn into the flow passage through the intake and propelled towards the outlet, the steam nozzle means having a flow passage of selectively variable size, and means for aerating the working fluid with an aerating gas prior to interaction of the driving fluid in the mixing zone whereby a three-phase fluid regime is created in the mixing zone by virtue of the interaction of the aerating gas, the water and the steam.