The global push towards sustainability has led to increased interest in alternative power sources other than coal and fossil fuels. One of these sustainable sources is to harness energy from the wind through wind turbines. However, a significant hindrance preventing the widespread use of wind turbines is the noise they produce. This study reviews recent advances in the area of noise pollution f...

The noise source mechanisms involved in motorcycling include various aerodynamic sources and engine noise. The problem of noise source identification requires extensive data acquisition of a type and level that have not previously been applied. Data acquisition on track and on road are problematic due to rider safety constraints and the portability of appropriate instrumentation. One way to add...

Abstract This paper will discuss a method of bluff body noise control that utilises the phenomenon of aerodynamic interference. This technique uses a second body (not necessarily bluff) that is placed in the wake of the bluff body whose noise we wish to control. Through proper understanding of the wake dynamics, the amplitude and phase of the noise from the downstream body can be controlled so ...

At the most fundamental level, main rotor loading noise is caused by the harmonically-varying aerodynamic loads (acoustic pressures) exerted by the rotating blades on the air. Rotorcraft main rotor noise is therefore, in principle, a function of rotor control inputs, and thus the forces and moments required to achieve steady, or “trim”, flight equilibrium. In certain flight conditions, the ensu...

Noise generated by turbulent boundary layers near the trailing edge of lifting surfaces continues to pose a challenge for many applications. Much of the previous work on this topic has focused on development of accurate computational methods for the prediction of trailing edge noise. For instance, aeroacoustic calculations of the flow over an airfoil using large-eddy simulation (LES) and aeroac...