Venturi Nozzle Turbine for High-Efficiency Fluid Energy Extraction

Background

The extraction of energy from fluid flows, particularly wind, is central to modern renewable power generation. Wind turbines convert kinetic energy from air movement into mechanical power using large rotating blades. As demand for sustainable solutions grows, improving the efficiency and reliability of fluid energy devices is critical for meeting escalating global electricity needs and reducing carbon emissions. However, fluctuating wind conditions, land constraints, and the push for higher capacity factors drive ongoing efforts to optimize fluid energy extraction technologies.

Conventional blade-based turbines face several limitations. Betz’s Law caps their theoretical energy capture at about 59%, and real-world performance often falls below 45% due to wake losses and suboptimal blade aerodynamics. Scaling rotor diameters to boost power output increases material costs, structural complexity, and maintenance demands. Additionally, turbines struggle to generate meaningful output at low wind speeds, exhibit noise and bird-impact concerns, and require significant siting areas. These challenges underscore a need for alternative methods to amplify captured fluid velocity and torque without relying solely on sweeping large rotor areas.

Technology

This device comprises a rotating hollow body that tapers from front to rear, collecting fluid through a frontal inlet and channeling it into one or more convergent/divergent nozzles. These internal venturi nozzles amplify fluid velocity via the nozzle effect before ejecting the high-velocity jet, typically at right angles to the central axis, producing thrust that drives continuous rotation. The resulting torque is transferred to an energy conversion system—such as an electrical generator or hydraulic pump—enabling power generation. By leveraging the cubic relationship between fluid velocity and power output, and allowing customizable nozzle geometries to suit specific fluid properties, the design achieves high efficiency across a range of conditions.

Traditional blade-based turbines are limited by Betz’s Law to about 59% efficiency, but this system sidesteps that barrier by internally accelerating the fluid to boost jet velocity beyond ambient levels, resulting in disproportionately higher power. A 50% velocity increase can theoretically quadruple output, surpassing linear gains from larger swept areas. Without external shrouds or oversized rotors, thrust is generated within the rotating body. Scalable from one to many nozzles and customizable with blade-shaped exteriors or circulation shrouds, it adapts to fluid density, pressure, and flow for optimal performance.

Benefits

• Significantly higher energy conversion efficiency by internally amplifying fluid velocity, bypassing Betz’s Limit
• Disproportionately greater power output leveraging the cubic relationship between fluid velocity and power
• Customizable convergent/divergent nozzle designs optimized for different fluids and operating conditions
• Scalable architecture with a variable number of nozzles and modular configurations
• Multi‐fluid applicability (e.g., wind and water) for versatile deployment
• Compact form factor with reduced swept area and potentially lower noise compared to traditional blades

Applications

• Utility-scale wind power generation
• Offshore wind farm turbines
• Marine current energy harvesting
• Micro-hydropower generation units
• Remote off-grid power systems

Additional info

A rotating hollow body narrows from inlet to rear, collecting wind or fluid through a front opening. Internal convergent/divergent nozzles accelerate the flow, ejecting high-speed jets typically perpendicular to the central axis. Resulting thrust drives cyclic rotation, transmitting torque to generators. Unlike blade turbines, it amplifies fluid velocity internally to exploit the v³ power relationship, enabling higher output. Customizable nozzle geometries adapt to various fluid densities, pressures and flow rates.