AquaShear™ Coanda screens

Dulas are the pioneers behind the ground-breaking AquaShear™ Coanda screen, which offers a low-cost operation and a unique solution that prevents clogging, maximises flow potential, and reduces the need for regular maintenance inspections.

Dulas provide technical expertise for large or high value installations that utilise AquaShear™ screens, and we are proud to say that these projects consistently deliver on their potential.

We offer ten AquaShear™ screen models. These vary in height and bespoke features. The type of screen used on any given project will depend on the head and width available on the intake site, as well as on the required flow rate. Dulas can advise on which screen would prove most suitable for your site.

Features and benefits

Features and benefits

  • AquaShear™ Coanda screens enable revenue to be maximised by increasing water flow.

  • They eliminate operational costs of erosion damage.
  • The screens exclude silt and debris greater than 1mm, enabling a low project maintenance.

  • AquaShear™ screens reduce capital costs by removing requirements for settling tanks.

  • They are easy to install, with no moving parts, will continue to operate at low temperatures without freezing and are aquatic life friendly

How AquaShear™ Coanda screens work

  • The screen is mounted on the downstream face of an intake weir. Water passes on to the screen via a specially designed acceleration plate, which provides an even distribution of flow and an increase in the water velocity.
  • As the water moves down the steep face of the screen at high velocity, excluded silt and debris is flushed away to continue downriver. The abstracted water passes through the screen and collects below in a chamber connected to the pipeline or intake channel.
  • The screen’s design means that only clean water can enter the intake system, while debris such as leaves, twigs and even fish eggs are excluded. The excluded debris remains in the river, eliminating any need to dispose of waste material.

How AquaShear™ Coanda screens are made

  • AquaShear Coanda™ screens are made from stainless steel. They consist of precisely positioned, finely spaced horizontal wedge wires built into a carefully designed screen.

  • The high capacity of the screen is achieved through a combination of two things: the Coanda effect (the tendency of fluid to cling to a surface) and the shear produced by the hydraulically sharp edges of the wedge wire.

High flow capacity – 140L a second per linear metre of weir length

AquaShear™ products

AquaShear™ Coanda single screens

AquaShear™ Coanda multiple screens

SSES automated Coanda screen cleaner

AquaShear™ case studies

Inverhaggernie Intake Refurbishment

Atholl Estates Run of River Hydro Scheme

Balnacarn Hydro Scheme

Iwrch Hydro Scheme Refurbishment

800kW Hydro scheme for Private Landowner

Doorian 310kW Intake rebuild

Hydro Refurbishment near Kinloch Rannoch

Frastanz Hydro Intake Refurbishment – Austrian Alps

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