Acoustic Noise Cancellation by Phase Alignment of Cooling Fans
Scott Guthridge, Richard E. Harper, Harry B. Marr, Bülent Abali · Annual IEEE Semiconductor Thermal Measurement and Management Symposium/Proceedings · 2007
With increasing power consumption of computer systems, faster and larger cooling fans are used and acoustic noise management becomes difficult. In this paper, we show that by locking a pair of cooling fan motors into a common frequency and 180 degrees out of phase, the dominant tone most perceptible by human ear can be reduced.