Aeroacoustics, flow noise, and flow-induced vibration

High speed airflows are the dominant source of noise from the airframes and engines of aircraft, but flow noise and flow-induced vibration are also major noise sources in many industrial machines. ISVR Consulting has wide experience in the measurement, mathematical modelling and engineering noise control for many types of flow-induced noise, ranging from aircraft wings and landing gears to industrial flues and vents.

Wind tunnel testing, with simultaneous noise source mapping and laser flow measurements can be performed in the University’s 11 ft × 8 ft (3.5 m × 2.6 m) and 7 ft × 5 ft (2.1 m × 1.5 m) wind tunnels at speeds of up to 45 m/s. At smaller scales, the ISVR anechoic chamber can be set up as an open jet acoustic wind tunnel. These facilities have been developed during the course of a number of research projects funded by the European Union and industry.

Scale model landing gear in a wind tunnel

Left:
A scale model aircraft landing gear mounted sideways in the 7 ft × 5 ft wind tunnel. The microphone array is installed behind the cloth screen on the right of the photo....

 

Flow noise contours arounfd scale model of landing gear

 ....providing a view of the noise sources on the bogie, as seen from the ground, shown by the noise contours plotted on the right.

Our experience gained from airframe noise research has been applied to many other problems, including the control of organ pipe resonances in boiler flues, suppression of flow induced vibration in air filtration systems and the modelling of aerodynamic noise sources on wind turbine generators.

Organ pipe resonances in a bolier flue

In each situation ISVR Consulting provided the understanding and measurement capability required to interpret the combined effects of fluid flow, acoustics and structural dynamics and to propose practical solutions. Where problems involve flow-induced resonances generating tonal noise, the solutions can often be both highly effective and low cost.