A Critical Review of Passive Noise Control Techniques in Industrial Fans

This review aims to assist engineers in understanding and applying passive solutions for reducing industrial fan noise. The paper systematically reviews the extant literature on passive noise techniques, with a particular focus on experimental rather than theoretical research. The review provides an assessment of the current state of the art in industrial fan flow and noise control. It offers a vision for potential improvements in noise reduction via novel application of flow and noise control technologies. The review examines the interaction between aerodynamic cause and acoustic effect and the application of control technologies that current cause and effect theories have inspired. The purpose is to provide a vision for aerodynamics research during the next decade that will serve as a basis for systematically reducing industrial fan noise emissions. The review provides an assessment of recent flow and noise control advances and considers some opportunities for future research. The review reflects an emphasis on low-speed industrial fans. The authors consider high-speed turbomachinery noise control, with the objective of illustrating the linkages between the two technologies. The review concludes with a summary of the opportunities for future research and its application to flow and noise control in industrial fan design.