Turbulence across thin objects

Typedefs
typedef struct SDTWindKarman	SDTWindKarman
	Opaque data structure for a thin obstacle object.
typedef struct SDTWindKarman	SDTWindKarman
	Opaque data structure for a thin obstacle object.

Functions
SDTWindKarman *	SDTWindKarman_new ()
	Object constructor. More...
void	SDTWindKarman_free (SDTWindKarman *x)
	Object destructor. More...
void	SDTWindKarman_setDiameter (SDTWindKarman *x, double f)
	Sets the diameter of the object. More...
void	SDTWindKarman_setWindSpeed (SDTWindKarman *x, double f)
	Sets the wind speed. More...
double	SDTWindKarman_dsp (SDTWindKarman *x)
	Signal processing routine. Call this function at sample rate to synthesize wind blowing against a thin object. More...

Detailed Description

An air flow hitting a thin object, such as a tree branch or a suspended wire, produces a singing or howling sound caused by a phenomenon known as Karman vortex street. This particular kind of turbulence is a repeating pattern of swirling vortices caused by the unsteady separation of flow of a fluid around the object. Karman vortex streets are modeled by white noise, passing through a bandpass filter with narrow bandwidth and high resonance.

Function Documentation

double SDTWindKarman_dsp

(

SDTWindKarman *

x

)

Signal processing routine. Call this function at sample rate to synthesize wind blowing against a thin object.

Returns

Computed audio sample

void SDTWindKarman_free

(

SDTWindKarman *

x

)

Object destructor.

Parameters

[in]

x

Pointer to the instance to destroy

SDTWindKarman * SDTWindKarman_new

(

)

Object constructor.

Returns

Pointer to the new instance

void SDTWindKarman_setDiameter	(	SDTWindKarman *	x,
		double	f
	)

Sets the diameter of the object.

Parameters

[in]

f

Diameter of the object, in m. Works best with very small values (< 0.1)

void SDTWindKarman_setWindSpeed	(	SDTWindKarman *	x,
		double	f
	)

Sets the wind speed.

Parameters

[in]

f

Wind speed, [0,1]