Ducted (Diffuser-Augmented) Turbine Concept

A duct (or diffuser) is a specially engineered shroud that surrounds the wind turbine’s rotor. Rather than allowing air to pass freely around the blades, the duct controls and channels airflow through the turbine.

By shaping and guiding the wind, the duct accelerates airflow as it passes through the rotor. This increase in wind speed directly improves energy capture, since available wind power rises with velocity.

Performance Validation

To quantify this effect, we run computational flow simulations. Our turbine design is placed inside a virtual wind tunnel with an inflow velocity of 7.5 m/s — the average wind speed in the UK.

By measuring average velocity across multiple points along the rotor diameter, we observe that airflow speed increases by approximately 13% as it passes through the duct.

Why a Ducted Turbine?

This is why we refer to our system as a ducted turbine concept:

• Increases the effective wind speed at the rotor

• Enhances overall energy capture

• Improves performance in moderate wind conditions

Additional Practical Advantages

Beyond performance improvements, the duct provides important practical benefits:

• Noise reduction – Makes the system more suitable for residential and commercial areas

• Improved safety – Helps reduce the risk of bird collisions with rotating blades

The Role of the Duct in GEM Technology

By combining aerodynamic acceleration with environmental and safety benefits, the duct plays a central role in GEM’s small-scale wind technology.