Fan noise can originate from multiple sources and is usually assessed using sound measurement methods. The main causes of fan noise and the ways to assess it include:

Air Turbulence:
As the fan blades rotate, they can disturb the airflow, creating turbulence that generates noise. The design of the blades and the housing structure play a significant role in determining the level of turbulence and the resulting sound.

Vibrations:
Imbalances in the fan blades, motor, or mounting components can lead to vibrations. These vibrations travel through the fan’s structure, amplifying the noise. Proper balancing and secure installation can help minimize this issue.

Airflow Obstructions:
Blockages or restrictions in the airflow path—such as clogged vents, dirty filters, or poorly positioned components—cause the fan to work harder, which increases noise levels.

Fan noise levels can vary depending on factors such as the fan type, operating speed, and the surrounding environment. Manufacturers usually provide noise specifications that offer guidance on expected sound levels under normal operating conditions.

风扇噪音可能来源于多个因素，通常通过声音测量方法进行评估。风扇噪音的主要原因及其评估方式包括：

空气湍流：
风扇叶片在旋转时，会扰动气流，产生湍流并发出噪音。叶片设计和外壳结构在决定湍流程度和产生的声音方面起着重要作用。

振动：
风扇叶片、电机或安装部件的不平衡可能导致振动。这些振动通过风扇的结构传播，放大噪音。适当的平衡和稳固的安装可以帮助减少这一问题。

气流阻碍：
气流通道中的堵塞或限制，例如通风口堵塞、脏滤网或组件位置不当，会迫使风扇更加努力工作，从而增加噪音水平。

风扇的噪音水平可能会根据风扇类型、运行速度和周围环境等因素有所不同。制造商通常会提供噪音规格，指导在正常工作条件下的预期噪音水平。