The scaling law for aerodynamic dipole type of sound from constrictions in low speed flow
ducts by Nelson and Morfey is revisited. A summary of earlier published results using this …

A prediction method for aerodynamic sound produced by the interaction of multiple elements
in a low speed flow duct has been developed. Same as the previous works of Mak and Yang …

A number of investigators have tried to develop a generalized prediction method for flow-
generated noise produced by in-duct elements in a ventilation system. Most of these …

The semi-empirical scaling law by Nelson and Morfey [1] predicts the noise generation from
constrictions in ducts with low Mach number flows. The results presented here demonstrate …

This paper studies the generation of noise by car ventilation systems whose outlet rates are
controlled by a butterfly valve and whose directions are controlled by grilles. First the noise …

Nelson and Morfey have derived an expression for the sound power radiated from an in-duct
spoiler subjected to the action of fluctuating drag forces arising from the flow turbulence in …

In recent years, there have been a number of attempts to devise generalized prediction
techniques for airflow-generated noise [1]. A technique based upon the static pressure loss …

Unavoidable discontinuities due to in-duct elements in a ventilation ductwork system result
in the generation of localized turbulence. Some of the turbulence energy is converted into …

Many duct systems transporting air flow also transport unwanted noise. The geometrical
parameters of duct bends can be tailored to reduce the noise emission by blocking sound …

A prediction method based on the theory of Nelson and Morfey for aerodynamic sound
produced by the interaction of two in-duct elements was developed by Mak and Yang. Their …