BeQuiet! Light Wings (BL072): Sturdy rotor with ARGB LEDs

Detaily BeQuiet! Light Wings (BL072)

Illuminated fans from BeQuiet! have the advantage over many competing models in a more robust rotor design. This is also due to the fact that it is not made of “light conductive” material and therefore some may not like the Light Wings fans, but aerodynamically they have the edge over other models. This is not only because of the choice of raw materials and their robustness, but also the overall shape of the blades.

Light Wings are the first BeQuiet! fans with ARGB LED elements. From their design, it is evident that BeQuiet! has its priority clear – fans must first perform their primary task, to which some tinsel in the form of lighting can then be attached. Therefore, the lightguide “only” skirts the rotor, which itself is made of a well-proven material. In the case of BeQuiet!, we mean PBT thermoplastic reinforced with fiberglass.

Fans with typically clear rotors, which conduct light well, do not achieve the rigidity of this composite, which naturally translates into inferior performance. A less rigid material at the same thickness and length is more flexible, which is undesirable for fans. Apart from possibly higher vibrations (and more unpleasant resonant frequencies in the sound), the static pressure and airflow are also lower due to deformations, especially in computers with negative system cooling on restrictive obstacles.

The Light Wings fan design tries to avoid the pitfalls mentioned in the text above as much as possible. Firstly, by using a relatively rigid material for the rotor, and secondly, by the fact that the blades themselves are relatively short and thick. These are all features that minimize torque undulation while running and therefore even at the maximum of 1670 rpm, which can already be considered a higher speed, the rotor does not transmit any vibrations to the frame.

While the blades are shorter, they also feature a more pronounced leading edge curve than more “common” geometries such as the Fractal Design Aspect 12 (PWM) or the Noctua NF-P12 redux-1700 (PWM). This is good, because it twists the trajectory of the air streams more and there is less friction (and thus less noise) in the areas around the frame. The blade spacing can be classified as average. The static pressure reported (and achieved) is also average relative to the speed. However, one cannot yet conclude “anything” on this basis, it is always important to correlate these parameters with a specific fixed noise level and with comparisons with other fans.

The surface of the blades has grooves on both sides, which is good for several reasons. One of them is the greater friction acting on the air streams. These don’t slide to the blade tips as much as on smooth surfaces (of other blades), and also these grooves offset airflow-reducing microturbulence on intake. This is true even at the hub, in the middle, where there is less turbulence, but still high enough to significantly stimulate resonant frequencies on a PC case grille in some cases.

On the intake side of the fan, the frame has protruding corners, but in such a way that there are no gaps between them through which air is lost. This is because these are filled by the construction of the circular light guide, which is extended in front of the rotor (so that the fan flawlessly fits flush on both sides). But this is only minimally so. SIt doesn’t create enough clearance for an unreinforced nylon dust filter. The latter rubs against the rotor, watch out for that.

The fan connects to the motherboard (or a fan hub) with a 4-pin connector (motor) and a 3-pin connector for the ARGB LED. The cables are long, half-meter long, and there are two connectors for lighting. One of them is ready for daisy chaining by connecting another fan in series. This comes in handy when installing fans on liquid cooler radiators, but also in a case if there are multiple fans side by side.

The tested model (BL072) of the Light Wings fan has 120 mm and a speed range of up to 1700 rpm. But BeQuiet! also has a faster one on offer „BL073“ (with a maximum of 2500 rpm).

* When reading performance values, a certain amount of tolerance must always be taken into account. For maximum speeds, ±10 % is usually quoted, minimum speeds can vary considerably more from piece to piece, sometimes manufacturers will overlap by as much as ±50 %. This must then also be adequately taken into account for air flow, static pressure and noise levels. If only one value is given in a table entry, this means that it always refers to the situation at maximum speed, which is achieved at 12 V or 100 % PWM intensity. The manufacturer does not disclose the lower limit of the performance specifications in its materials in that case. The price in the last column is always approximate.

• Contents
• Detaily BeQuiet! Light Wings (BL072)
• The basis of the methodology, the wind tunnel
• Mounting and vibration measurement
• Initial warm-up and speed recording
• Base 6 equal noise levels…
• ... and sound color (frequency characteristic)
• Static pressure measurement…
• … and airflow
• Everything changes with obstacles
• How we measure power draw and motor power
• Measuring the intensity (and power draw) of lighting
• Results: Speed
• Results: Airlow w/o obstacles
• Results: Airflow through a nylon filter
• Results: Airflow through a plastic filter
• Results: Airflow through a hexagonal grille
• Results: Airflow through a thinner radiator
• Results: Airflow through a thicker radiator
• Results: Static pressure w/o obstacles
• Results: Static pressure through a nylon filter
• Results: Static pressure through a plastic filter
• Results: Static pressure through a hexagonal grille
• Results: Static pressure through a thinner radiator
• Results: Static pressure through a thicker radiator
• Results: Static pressure, efficiency by orientation
• Reality vs. specifications
• Results: Frequency response of sound w/o obstacles
• Results: Frequency response of sound with a dust filter
• Results: Frequency response of sound with a hexagonal grille
• Results: Frequency response of sound with a radiator
• Results: Vibration, in total (3D vector length)
• Results: Vibration, X-axis
• Results: Vibration, Y-axis
• Results: Vibration, Z-axis
• Results: Power draw (and motor power)
• Results: Cooling performance per watt, airflow
• Results: Cooling performance per watt, static pressure
• Airflow per euro
• Static pressure per euro
• Results: Lighting – LED luminance and power draw
• Results: LED to motor power draw ratio
• Evaluation