"Grivo JetStar"


"The ultimate ship propulsion system"


"State of the art high performance Water Jet Propulsion"

Starting with the facts about today's so called water jets. Such water jets are just centrifugal/impeller pumps that accelerate the water to limited nozzle speed of about 80 knots, ((45 m/sec.) With every knot (0.514 m/sec.) the vessel increases its speed; the nozzle speed loose this quantity. Meaning, has the vessel reached 40 knots (20.6 m/sec.), the water jet nozzle speed of 80 knots declined 40 knots, while the vessels resistance increases dramatically. As we know, the nozzle speed is in this devices limited, and we can only get more thrust by pumping more water. Mass x Speed is thrust with reference to the 3rd law of motion by Isaac Newton.

In case we use for more thrust a larger water jet, the engines have to be also larger, as well as the tanks. The vessel becomes heavier, the resistance increases, and it is often no more as fast as before, a difficulty without end.The problem is the restricted nozzle speed and water flow.

This problem has been solved by the "Grivo JetStar", a water jet that works on basic of the patented High Performance Displacement pump "Grivo Star Pump". The pump works like an infinity piston in a cylinder. We can easily reach 200 knots (103 m/sec.) nozzle speed, and have no problem with nozzle speed loss, as above mentioned. We push just a little the throttle. It is a real Jet. The limits are material limits, or set by common sense.

The Grivo JetStar is the only real innovation in ship propulsion!

It has remarkable more performance in comparison with today’s Water Jets, which represent  a system that was invented in the17th Century, exactly in the year 1660, by Toogood and Hays.

Excel Simulations Software available.

Picture shows 4 "Seatek" high performance marine engines, powering 2 Grivo JetStar Waterjets




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