Due to their high power and huge blades, HVLS Fans inevitably produce noise during operation, and most of the noise is generated by the rotation of the blades. Generally speaking, the greater the power, the larger the blades, and the larger the blades, the greater the wind power. When Hvls Ceiling Fans motors of the same size have different powers, choose a larger one because it has sufficient power and is more durable. However, HVLS Fans are powerful, consume more power, and become louder. The correct choice should be to look at the wind volume, because everyone's perception of wind is different.
For industrial production, such noise has little impact, but for commercial occasions, if the noise is too high, it will seriously affect people's feelings, so some solutions need to be studied to reduce the noise generated by the fan blades.
1. Change the tip vortex noise reduction.
When the blade rotates, the pressure difference between the tip pressure surface and the suction surface causes the pressure surface airflow to bypass the blade tip surface and flow into the suction surface, which not only destroys the two-dimensional flow of the blade tip, but also generates tip vortices. Research on tip vortex intensity and control methods shows that tip vortices are one of the main sources of aerodynamic noise in HVLS Fans blades, and it is feasible to install "winglets" and "flaps" on the blade tips.
2. Damping, shock absorption and noise reduction
Damping and noise reduction technology utilizes the characteristics of damping materials and the reasonable design of the damping structure to dissipate the vibration energy of structural components to achieve the purpose of damping and noise reduction. Most of the blades of HVLS Fans adopt a hollow thin-walled structure, and partial and complete free damping can be performed in the housing from the rear end to the blade tip of the violently vibrating blades. For example, filling and attaching damping materials consumes energy through the interaction between vibration waves and damping materials or damping structures, which attenuates blade vibration and reduces noise.
3. Change the blade shape and chord length to design noise reduction
In blade design, the chord length of the blade root can be appropriately reduced without affecting other characteristics. On the other hand, the noise generated by HVLS Fans blades tends to increase as the blade tip chord length increases. In order to reduce noise, the blade tip chord length can also be appropriately reduced. In order to ensure that the power is not reduced, the area from the middle to the middle and rear of the blade should be appropriately enlarged.
4. Limit the linear speed of the suction head to reduce noise
Generally speaking, blade aerodynamic noise is proportional to the fifth power of the blade tip linear velocity. When designing blades, it is necessary to coordinate the relationship between blade length and speed. For mature blades, the noise can be reduced by reducing the rotation speed if necessary, but a certain amount of air volume will generally be lost.
