Muddala Suryanarayana Murthy; Mohamed Gafar Ahmed Elnourani MEE09:39, pp. 66. TEK/avd. för signalbehandling, 2009.
This thesis work aims at investigating the use of an active noise control (ANC) system on a radial fan. This was done by studying the fan structure and its potential working environment (the ducts). This includes measuring the sound levels on several positions and select suitable positions to apply the ANC system. Moreover, the tested ANC system was implemented on the ventilation system and acceptable results were obtained. Further analyses were made based on the obtained results and some explanations were derived to investigate the reason behind the ANC systems incapability to attenuate the noise generated by the fan at some frequencies.