Aero-Acoustical Effects of Some Parameters of a Backward-Curved Centrifugal Fan Using DoE.

Effects of the entrance parameters and their interactions on the noise reduction, static head, mass flow rate, rotational speed, and efficiency of a backward-curved centrifugal fan have been studied experimentally. Design of Experiment (DoE) method has been performed to analyze the results and their effects. Three different levels for the entrance curvature and two levels for the shape of blades passage, shroud, number of blades, and inlet bell position have been selected to design and construct different fans for the aero-acoustic experimental measurements. The results analysis shows that to have a lower noise and higher efficiency, higher entrance curvature, hyperbolic profile for the shape of shroud, and inlet bell position 1 (no radial clearance) must be selected. However, based on the priority of the noise reduction or efficiency increase, constant deceleration for the blade passage or a logarithmic profile for the blades passage should be chosen. The interactions of these selections have a positive effect on noise reduction as well as on efficiency. [ABSTRACT FROM AUTHOR]