OPTIMIZATION OF THE AERODYNAMIC AND AEROACOUSTIC CHARACTERISTICS OF A SMALL CENTRIFUGAL FAN BY MEANS OF INVERSE DESIGN AND EVOLUTIONARY ALGORITHMS

摘要

In this work, the inverse design code TURBOdesign 1 has been used in a direct approach to optimize both the aerodynamic and aeroacoustic properties of a small centrifugal fan with backward-curved blades. Two promising fan designs along with a reference fan have been investigated numerically using CFD and the results have been validated experimentally using a chamber test rig for the aerodynamics and the in-duct method for acoustics. A design aiming for good aerodynamic performance showed an increased efficiency in a wide operating range of about 5 to 10%. Another design aiming for low noise showed a numerically determined reduction in the overall sound radiation of 1 dB on average. This trend could not be reproduced in the experiments, instead the high efficiency design showed the best acoustic characteristics in a wide frequency range, which is why this is a subject of ongoing research.