Active Noise Control In An Air Duct Flow Control Loop: A Technical Approach For Improving The Working Environment
In many acoustic problems low frequency noise is dominant and in such cases passive sound absorber is not effective as that of active noise control. This paper aims to cancel the noise created by the induction motor –fan assembly used in the air duct flow system. Here, active noise control (ANC) technique was used for reducing the acoustic noise produced by the system. Active noise control was achieved by introducing the anti-noise with the help of an efficient secondary source, appropriate electronic control unit, electro acoustic transducers and sensors. Active noise control has pretty number of applications to a wide variety of acoustic problems in manufacturing, industrial operation, etc. In this paper, an attempt has been made to deal with real world noise (noise produced by the motor) and analyzed the noise produced in the control system. The performance of the noise control system with the implementation of FX-LMS algorithm was represented.An adaptive filter with filter length 300 and LMS step size of 0.0002 was used to reduce motor-fan related noise of an air duct flow system and finally a lower noise amplitude was obtained after active noise control.
Keywords—air duct flow system; active noise control; adaptive filters; electro-acoustical transducers; FX-LMS algorithm