New DYNA-FOIL™ Stabilizer System
The DYNA-FOIL™ provides exceptional roll reduction for vessels at both Zero Speed™ and underway.
The stabilizer system utilizes a unique foil design that allows for a dynamic self-induced lift for outstanding Zero Speed™ operation and a highly efficient lift-to -drag coefficient for superior underway operations.
Quantum, (known for pioneering Zero Speed™ stabilization in 1999), has spent several years developing the product which included extensive multiple third party testing such as the MARIN (Marine Research Institute Netherlands), creating new stabilizer technology which now expands their product line and allows for more flexibility in the application of ship stabilization and ride control.
Previously, a typical fixed fin stabilizer is limited in size to the “beam-keel” envelope (hull envelope), and should NOT protrude outside of this boundary area. Therefore, it can be problematic if a ship requires very large fins. The new DYNA- FOIL™ (along with their other recent technology, such as Quantum’s MAGLift™ ), is not limited to this parameter, since the foil retracts completely into a full pocket or to a parallel position to the hull (non-pocketed model) when not in use.
Another benefit of being fully retractable is in the application of ice-class vessels operating in extreme conditions, where a stabilizer is required but needs to be completely stowed to avoid potential damage from contact with any ice.
How the DYNA-FOIL™ works (for Zero Speed™ ): Counter to a traditional fixed fin system for Zero Speed™, (which uses a “paddling” action), Quantum’s DYNA-FOIL™ uses the hydrodynamic lift generated by water flow over the foil from a swing action of the unit. This action creates water flow over the surface of the foil thus generating lift. The direction of swing determines the direction of lift force generated. Both the angle of attack and the swing speed are controlled variables that are adjusted to provide the optimum stabilization. While the concept is relatively simple and very similar to the principles of the MAGLift™ system, the implementation and possibilities for optimization of the system are extensive.
For Underway: The foil is deployed at 90 degrees to the hull centerline, and lift is generated much like traditional systems by articulating the foil thus changing its angle of attack through the water flow and generating lift. However, the DYNA-FOIL™ has the added advantage of having a unique foil profile. This profile allows high lift force to be generated at low angles of attack but with minimal resistance; hence maximum lift with minimal drag. This coupled with the mechanical properties of the actuation mechanism (dynamic foil positioning), provide for an almost instantaneous positioning of the foil thus improving lift force timing which in itself is critical to maximizing roll reduction with minimal effort.
Performance and Efficiency: At Zero Speed™ can be measured by the stabilizing moment generated in kNm.
In the case of the DYNA-FOIL™ there are a number of factors that contribute to the performance and efficiency of the system providing key advantages over a traditional fin system.
- The lever arm is much larger.
- The down angle positioning of the hull unit is not governed by the hull profile therefore attaining the most efficient down angle is generally possible with the DYNA-FOIL™ .
- Higher lift coefficients and better lift-to-drag ratios of the foil compared to that of low aspect fixed fin increase foil efficiency, i.e. The stabilizer moment generated by the DYNA-FOILl™ is up to 150% greater than those by a standard fixed fin at Zero Speed™ of the same size.
Flexibility of Installation: To accommodate multiple types of hull forms and mission profiles the DYNA-FOIL™ is available in both a fully pocketed version as well as a non-pocketed version.
Pocketed: For vessel that require ice class or have a high block coefficient where an externally mounted appendage is not desirable Quantum offers the DYNA-FOIL™ in a completely pocketed version.
Non pocketed: For high speed hard chine vessels where space and weight in the vessel is critical the DYNA-FOIL™ can be supplied in a non-pocketed version. To make this version usable for high speed applications Quantum has optimized the stowed profile of the unit up to 30 Knots by way of CFD (computational fluid dynamics).
The DYNA-FOIL™ uses a newly designed and engineered dedicated CHPU (Compact Hydraulic Power Unit) system to power the stabilizers. This brings together tried and tested hardware with a new approach to power management and power saving. Through the stored energy accumulators and variable motor control the CHPU can provide power to the DYNA-FOIL™ with extremely low power cycling on the ship’s net.
By using an in tank submerged pump, airborne noise is reduced without the use of sound shields. Structural born noise is handled with both mechanical absorption and hydraulic suppression hardware. Each individual hull unit receives its own standalone power unit complete with touch screen for diagnostics and controls locally and remotely through any Quantum interface on the ship. This allows for complete redundancy between hull units.