German propulsion specialist SCHOTTEL launched a newly developed variant of its rim thruster (SRT). Covering the power range up to 500 kW, the new retractable rim thruster (SRT-R) offers low noise emissions and tailor-made solutions for a wide range of applications. Optimized by computational fluid dynamics (CFD), the internal propeller blades are hydrodynamically designed to be highly resistant to cavitation.
The SRT-R is able to cover a thrust radius of 360 degrees. This not only makes it more versatile, but also allows it to be optimally adapted to any requirement and operation profile, including dynamic positioning (DP) operation or as a take-home device. In retracted position, no additional flow resistance is generated.
Like the SRT, the SRT-R also features low-level noise and vibration. This makes the thruster particularly suitable for all vessels regularly carrying passengers, such as yachts or cruise vessels with high demands on comfort.
The retractable rim thruster is also available as an RT variant. This means that in retracted position it also functions as a transverse thruster, making it highly effective in shallow water. Characterized by improved maneuverability, its range of application extends from brief docking and casting-off in ports to continuous operation with dynamic positioning; for example, for following the sun in DP mode for yacht applications. It also stands out due to its short response time to steering commands that make precise dynamic positioning easier at all times.
The SRT, one of SCHOTTEL’s latest developments, is an electric propulsion system. The electric motor stator is installed in the outer part of the tunnel, while the propeller blades are attached to the inside of the rotor. This results in a space-saving and low-weight thruster. It converts electric power directly into propulsion power. Surrounding water permanently cools the electric motor, preventing it from overheating.
Thanks to its robust design, the SRT guarantees that maintenance efforts are effectively reduced. Furthermore, it is suitable for new builds and retrofits due to its compact design and simple installation.
Offering the option of using biodegradable oils, vessels with the SRT-R are compliant with the current Vessel General Permit (VGP) regulations of the U.S. Environmental Protection Agency (EPA).
The first SRT units as well as the retractable variant are already proving their reliable operation on different types and sizes of vessels.