Our AAO (Advanced Acoustic Optimisation) frames feature integrated anti-vibration pads as well as our proprietary Stepped Inlet Design and Inner Surface Microstructures, both of which further refine the fan’s performance/noise efficiency.
The NF-S12A’s Anti-Stall Knobs reduce flow separation phenomena in medium to high impedance situations and thereby increase the fan’s stall margin. This means that the NF-S12A is even more versatile than its renowned predecessor and can achieve better performance on heatsinks and radiators.
Bevelled Blade Tips
Reducing critical rotor stator interaction, the NF-S12B's and NF-B9's Bevelled Blade Tips permit to combine a higher blade surface area with quieter operation and thus form a cornerstone of the fans' outstanding efficiency.
Flow Acceleration Channels
By speeding up the airflow at the crucial outer blade regions, Flow Acceleration Channels reduce suction side flow separation and thus lead to better efficiency and lower vortex noise.
Focused Flow™ Frame
Designed for pressure demanding applications such as heatsinks and radiators, the Focused Flow™ frame features eleven stator guide vanes that straighten, channel and focus the airflow, which allows the NF-F12 to rival the performance of conventional fans running at much faster speeds.
Inner Surface Microstructures
With the tips of the fan blades ploughing through the boundary layer created by the Inner Surface Microstructures, flow separation from the suction side of the blades is significantly suppressed, which results in reduced blade passing noise and improved airflow and pressure efficiency.
Metal bearing shell
In order to guarantee the highest possible degree of manufacturing precision, minimum tolerance and excellent long-term stability, our newest 120 and 140mm fans sport a CNC milled bearing shell made entirely from brass.
Custom-designed PWM IC with SCD
Our custom-designed NE-FD1 PWM IC integrates our Smooth Commutation Drive (SCD) technology. By providing smoother torque impulses, SCD suppresses PWM switching noises and thus makes the fan quieter at low speeds.
Smooth Commutation Drive
The latest version of our advanced Smooth Commutation Drive system ensures superb running smoothness by eliminating torque variations and switching noises. This makes our fans remarkably quiet even at very close distances.
Combining the proven concept of hydrodynamic bearing with an additional magnet that supports the self-stabilisation of the rotor axis, our time-tested SSO-Bearing technology has become synonymous with supremely quiet operation and exceptional long-term stability.
SSO2 is the further optimised second generation of our renowned, time-tested SSO bearing. With SSO2, the rear magnet is placed closer to the axis to provide even better stabilisation, precision and durability.
Stepped Inlet Design
Our Stepped Inlet Design adds turbulence to the influx in order to facilitate the transition from laminar flow to turbulent flow, which reduces tonal intake noise, improves flow attachment and increases suction capacity, especially in space restricted environments.
Vortex-Control Notches split up trailing edge vortices and thus spread the fan’s noise emission over a wider range of frequencies. This measure makes the fan sound more pleasant to the human ear.
Sterrox® liquid-crystal polymer (LCP)
Noctua’s novel Sterrox® liquid-crystal polymer (LCP) compound features extreme tensile strength, an exceptionally low thermal expansion coefficient and dampening characteristics that are ideal for reducing resonance and vibration phenomena in advanced fan-blade designs.
Inner Surface Microstructures
Inner Surface Microstructures are an advanced aerodynamic design measure first introduced with Noctua’s NF-F12 fan. Miniature dents at the inside of the fan frame create a turbulent boundary layer when the fan blades pass by. With the tips of the fan blades ploughing through this boundary layer, flow separation from the suction side of the blades is significantly reduced.
As suction side flow separation is a major source of axial fan blade passing noise and leads to considerable losses in airflow and pressure efficiency, the use of Inner Surface Microstructures allows for lower noise emission and better performance at the same time. Reducing undesired turbulences caused by suction side flow separation, Inner Surface Microstructures help Noctua’s latest fans to keep pushing the boundaries in performance to noise efficiency.