The noise measurement of computer cooling fan mainly involves several key parameters and concepts. The following is a detailed explanation of the noise measurement of computer cooling fan:
1. Noise unit: decibel (dB)
The noise of computer cooling fan is usually measured in decibel (dB). The decibel is a logarithmic unit used to express the relative size of sound intensity. It is based on the human ear's perception of sound and takes into account the sensitivity of the human ear to sounds of different frequencies.
2. Sound power level (Lw):
The sound power level (Lw) of computer cooling fan is an important parameter. It indicates the total sound power generated by the fan in dB (A). "A" stands for A weighting, which is a correction value after considering the sensitivity of the human ear to sounds of different frequencies. This parameter helps us understand the overall noise level generated by the fan when it is running.
3. Noise test method:
The noise test of computer cooling fan is usually carried out in a specific anechoic room, and the background noise must be below a certain level (such as 18.5dB (A)). During the test, the fan runs in free air, and a noise meter is placed one meter away from the fan inlet to measure the noise level.
4. Noise calculation of multiple fans:
When multiple fans are working at the same time, their noise will interfere with each other. For fans running in the same phase (same frequency, phase difference is 0), their sound power levels can be logarithmically added to calculate the total noise level. The noise calculation of fans running out of phase is more complicated, and the effect of phase difference on noise needs to be considered.
The noise measurement of computer cooling fans is a process that comprehensively considers multiple factors, including sound power level, test environment and method, and noise calculation method when multiple fans are running at the same time. Decibel as a unit of measurement can help us objectively understand the noise level of the fan, so as to choose a product that better suits our needs. In practical applications, factors such as the frequency characteristics, spatial distribution and human hearing characteristics of noise also need to be considered to more comprehensively evaluate the noise performance of computer cooling fans.
