Abstract— Performance of axial fan is found to reduce drastically when instability is encountered during its operation. Performance of an axial fan is severely impaired by many factors mostly related to system instabilities due to rotating stall and surge phenomenon experienced during its operation. The present work involves measuring the sound spectrum measurements in ducted axial fan under stall conditions at frequency range from 9000 Hz to 9600 Hz. Objective of the experiment is to measure the frequency domain signal and study the sound Characteristics in ducted axial fan by using spectrum analyser. Different types of FFT signals have been measured under stall conditions for the frequency range of 9000 Hz to 9600 Hz with respect to rotor speed and different graphs are plotted for ducted axial fan.

Index Terms— Microphone, BNC connector, Data Acquisition System, LABVIEW, Spectrum Measurements, Throttle position, Rotor speed

Cite: Manikandapirapu P K, Srinivasa G R, Sudhakar K G, and Madhu D, " Sound Spectrum Measurements in Ducted Axial Fan under Stall Conditions at Frequency Range from 9000 Hz to 9600 Hz," International Journal of Mechanical Engineering and Robotics Research, Vol. 1, No. 2, pp. 190-195, July 2012.