Collerette de reduction de turbulence pour sunon 40x40- turbulence reduction flange for sunon 40x40

thingiverse

Turbulence reduction collar designed to be used with a sunon fan 40x40x10 (or 20). It suppresses the slight whistling of air when it enters the fan. It also greatly reduces noise in case of backflow caused by a bottleneck. No reduction in flow observed: putting your hand in front, you don't feel a less powerful breath, and a sheet of light weight is blown with as much intensity with this collar as without. The cap is optional and a bit difficult to remove. Place for measurements: Idle (sunon not installed on the fang, breath in the void), noise does not vary and remains constant at 38dB. I made the measurement on my mobile phone with the "sonomètre" app without origin device. The relative measure shows that there is no difference (which would have been identical with origin device). For info, the noise is measured at 30dB when the printer is off. Once the fan is screwed on, the measured noise goes from 40dB (without collar) to 38dB (with collar) on my fang -> a difference of 2dB. The noise reduction is not negligible and reduced to an "idle" level. For info, if we measure the noise generated by a source and that we double that same source, the measurement increases about 3dB. It is difficult to give a value on ear, but for me it is clearly identifiable: the sharp noise issued by the fan undoubtedly decreases. Concerning flow velocity measured with a Trotec TA300 anemometer: without the collar it is measured at 5.6 m/s and with the collar it is measured at 5.6 m/s at the same anemometer position. No difference! The use of this collar has no impact on air flow delivered by the fan but it reduces its noise without side effects (IN MY CASE, WITH MY INSTALLATION), unlike this silent widely used by many people that unfortunately decreases by 37% the flow rate (measurements for proof) ...