Henan axial fan manufacturers Company Name: Henan Hong Blower Co., Ltd. Company website: www.henanhongjifengji.com Sales Department: 0394-7892627 15518086290 QQ: 445528270 For fans, the point source model is a very useful technique. This approximate guideline, the highest frequency wavelength λ should be studied much larger than the physical dimensions of the sound source L. In order to meet the requirements of this criterion, to transmit high frequency noise of the blades, in the application of point source model, each of the relevant area can be regarded as isolated or related to the volume of the sound source of a small size,