IntelliJET Development History

Intelligent Inlet Duct

The intelligent inlet duct adjusts to recover the velocity head of the incoming water at all planing speeds and at all throttle positions. This higher inlet efficiency is most important in designs based on larger jets. Larger jets, in turn, are desirable because they produce more thrust at low boat speeds. This parallels engine development in commercial aircraft where high-bypass turbofans move more air through a larger jet for shorter takeoffs.

This combination of larger jet size, efficient inlet duct, and variable nozzle allows a 50 to 80% increase in low speed thrust, while increasing top speed and maintaining higher propulsion efficiency at all boat speeds and accelerations. These three innovations work together to approach the limits of propulsion efficiency.

See below for "The System and How it Works" and "Why it all Works Together".

Essential Performance Features

Larger flow
for increased thrust.
Intelligent inlet
for power recovery.
Adjustable nozzle
for pump efficiency.

Practical Engineering Features

Inlet molded in boat hull.
Flexible motor placement.
Engineered for ease
of installation.

*The System and How It Works.* Back to Top
	Larger Jet Size increases propulsion efficiency using technology demonstrated in development of larger jets in aerospace industry.
Full Throttle at 15 mph
	Intelligent Inlet Duct automatically adjusts to recover the power of the incoming water at all planing speeds and at all throttle positions.
Full Throttle at 35 mph
	Variable Rectangular Steering Nozzle allows simultaneous control of nozzle area and steering direction to maintain peak efficiency over wide ranges of boat speed, pump shaft speed and steering vectors.
Full Throttle at 50 mph

Why It All Works Together

Bigger jets are desirable because they create higher thrust. But the bigger the jet, the more power that is lost in the ordinary inlet duct. This power loss has to be made up by the motor and the pump.

The adjustable inlet duct reduces this power loss. And, as the inlet duct becomes more efficient, it increases pressure on the nozzle, which results in higher flow through the system.

But, higher flow through the system results in reduced pump efficiency. Hence the need for the variable nozzle to regulate the system flow for pump efficiency.

Summary: Using the combination of these three innovations means a high volume of water, an efficient inlet duct and an efficient pump operation under all operating conditions.

The Variable Nozzle

The variable rectangular steering nozzle allows simultaneous control of nozzle area and steering direction to maintain peak efficiency over wide ranges of boat speed, pump shaft speed and steering vectors.

Company History

The development of IntelliJet Marine, Inc. began when current president, Jeff Jordan, was considering the purchase of a manufacturer of aluminum jet river boats. Mr. Jordan had previously spent ten years in the design and manufacture of small commercial hydroelectric systems, during which time he observed several causes of hydraulic inefficiency in the marine jet propulsion systems.

Any such cause of inefficiency is rigorously attacked in the hydroelectric business because it translates into power not generated and revenue lost. In jet boats it translated into the need for a flatter hull, a bigger motor and a bigger fuel tank.

The application of hydroelectric design principles to jet boats resulted in three broad patents covering the inlet, pump and nozzle control conditions that must be maintained for efficient marine jet propulsion.

The Patents

To view the patents, go to: http://www.uspto.gov/patft/index.html

Click on Patent Number Search.

Enter a patent number noted below.

#5,658,176       “Marine Jet Propulsion System”

#5,679,035    “Marine Jet Propulsion Nozzle and Method”

#5,683,276       “Marine Jet Propulsion Inlet Duct and Method”

#7,241,193 B2 "Variable Marine Jet Propulsion - July 10, 2007 (Click here for .pdf)

IntelliJet Marine, Inc.
4805 158th Court NE
Redmond, WA 98052-5261
425-869-2723
info@intelliJetMarine.com

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