SSO-Bearing

AAO Frame

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.

Anti-Stall Knobs

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.

SSO-Bearing

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 Bearing

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

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.

SSO-Bearing

Thanks to an optimised principle of operation, the self-stabilising oil-pressure bearing (SSO bearing) surpasses current types of ball, sleeve or liquid bearings in terms of long-term stability and quietness.

SSO principle of operation

The rotary motion of the axis generates pressure upon the special oil enclosed within the bearing. This causes the build-up of a dynamic pressure field that centres and stabilises the axis within the bearing shell. While conventional liquid bearings employ the principle of hydrodynamic pressure too, the SSO bearing is equipped with an additional magnet that supports the self-stabilisation of the rotor axis. This allows for a faster, more precise and more reliable centring of the rotor axis and thus increases the long-term stability and quietness of the bearing: When the fan starts, the dynamic pressure field of the liquid bearing needs to build up first, which results in an initial precession of the axis, the so called gyro effect. This amounts to an increased abrasion until the axis is stabilised through the build-up of the dynamic pressure field, which may by and by lead to increased noise emission and bearing defects. Because of this, the SSO bearing possesses a built in magnet, whose field ensures the immediate self-stabilisation of the rotor and hence reduces the gyro effect. In addition to the stabilisation during the start-up phase of the fan, the supporting magnet allows for a more exact centring of the axis within the bearing shell and thus further reduces bearing resistance, abrasion and noise emission.
SSO compared to conventional sleeve and ball bearings

The sleeve and ball bearings currently predominating the fan market exhibit major drawbacks: While conventional sleeve bearings initially have very low noise emissions, they mostly possess unsatisfying long-term stability, which leads to a short overall lifespan and increasing noise after longer operating times. High grade ball bearings, on the other hand, while providing satisfying long-term stability operate at slightly higher noise levels from the beginning. The SSO bearing not only surpasses the quietness of conventional sleeve bearings but also the long-term stability of current top-of-the-line ball bearings.