JACOUSTICS::JSoundVelocity Struct Reference

Implementation for depth dependend velocity of sound. More...

#include <JSoundVelocity.hh>

Inheritance diagram for JACOUSTICS::JSoundVelocity:

Public Member Functions
	JSoundVelocity (const double a, const double b, const double z0)
	Constructor.
JSoundVelocity &	set (const double z0)
	Set depth.
JSoundVelocity	operator[] (const double z0) const
	Get sound velocity at given depth.
virtual double	operator() () const override
	Get velocity of sound at seabed.
virtual double	operator() (const double z) const override
	Get velocity of sound at given depth relative to seabed.
virtual double	getDistance (const double t_s, const double z1, const double z2) const override
	Get distance travelled by sound.
virtual double	getTime (const double D_m, const double z1, const double z2) const override
	Get propagation time of sound.
virtual double	getInverseVelocity (const double D_m, const double z1, const double z2) const override
	Get inverse velocity of sound.

Private Attributes
double	a
double	b
double	z0

Friends
std::istream &	operator>> (std::istream &in, JSoundVelocity &velocity)
	Read sound velocity from input.
std::ostream &	operator<< (std::ostream &out, const JSoundVelocity &velocity)
	Write sound velocity to output.

Detailed Description

Implementation for depth dependend velocity of sound.

Note that

• z-axis is pointing upwards; and
• velocity is defined at a given depth.

It is assumed that the dependence of the sound velocity on the depth is non-zero.
The depth is commonly referred to as the seabed.

Definition at line 35 of file JSoundVelocity.hh.

Constructor & Destructor Documentation

JSoundVelocity()

JACOUSTICS::JSoundVelocity::JSoundVelocity ( const double a, const double b, const double z0 )

inline

Constructor.

Note that the depth is relative to the sea surface and therefore should be negative.

Parameters

a	velocity [m/s]
b	d(v)/d(z) [m/s/m]
z0	depth [m]

Definition at line 47 of file JSoundVelocity.hh.

                                                                    :
      a (a),
      b (b),
      z0(z0)
    {}

Member Function Documentation

set()

JSoundVelocity & JACOUSTICS::JSoundVelocity::set ( const double z0 )

inline

Set depth.

Note that the depth is relative to the sea surface and therefore should be negative.

Parameters

z0

depth [m]

Returns

this sound velocity

Definition at line 62 of file JSoundVelocity.hh.

    {
      this->a  += this->b * (z0 - this->z0);
      this->z0  = z0;
      
      return *this;
    }

operator[]()

JSoundVelocity JACOUSTICS::JSoundVelocity::operator[] ( const double z0 ) const

inline

Get sound velocity at given depth.

Note that the depth is relative to the sea surface and therefore should be negative.

Parameters

z0

depth [m]

Returns

sound velocity

Definition at line 79 of file JSoundVelocity.hh.

    {
      return JSoundVelocity(*this).set(z0);
    }

operator()() [1/2]

virtual double JACOUSTICS::JSoundVelocity::operator() ( ) const

inlineoverridevirtual

Get velocity of sound at seabed.

Returns

velocity [m/s]

Implements JACOUSTICS::JAbstractSoundVelocity.

Definition at line 90 of file JSoundVelocity.hh.

    {
      return a;
    }

operator()() [2/2]

virtual double JACOUSTICS::JSoundVelocity::operator() ( const double z ) const

inlineoverridevirtual

Get velocity of sound at given depth relative to seabed.

Parameters

z

depth [m]

Returns

velocity [m/s]

Reimplemented from JACOUSTICS::JAbstractSoundVelocity.

Definition at line 102 of file JSoundVelocity.hh.

    {
      return a + b * z;
    }

getDistance()

virtual double JACOUSTICS::JSoundVelocity::getDistance ( const double t_s, const double z1, const double z2 ) const

inlineoverridevirtual

Get distance travelled by sound.

The distance travelled is obtained by consistency with method JSoundVelocity::getTime.
Note that the depth is relative to the seabed.

Parameters

t_s	time [s]
z1	depth [m]
z2	depth [m]

Returns

distance [m]

Implements JACOUSTICS::JAbstractSoundVelocity.

Definition at line 119 of file JSoundVelocity.hh.

    {
      const double eps = 1.0e-8;
 
      const double v1  = (*this)(z1);
      const double v2  = (*this)(z2);
      const double lv  = log(v2/v1);
 
      if (fabs(lv) > eps)
        return t_s * fabs((z2 - z1) * b / lv);
      else
        return 0.5 * t_s * (v1 + v2);
    }

getTime()

virtual double JACOUSTICS::JSoundVelocity::getTime ( const double D_m, const double z1, const double z2 ) const

inlineoverridevirtual

Get propagation time of sound.

The propagation time is obtained from the integral .
Note that the depth is relative to the seabed.

Parameters

D_m	distance [m]
z1	depth [m]
z2	depth [m]

Returns

time [s]

Implements JACOUSTICS::JAbstractSoundVelocity.

Definition at line 147 of file JSoundVelocity.hh.

    {
      const double eps = 1.0e-8;
 
      const double ct  = (z2 - z1) / D_m;
      const double v1  = (*this)(z1);
      const double v2  = (*this)(z2);
 
      if (fabs(ct) > eps)
        return fabs(log(v2/v1) / (ct*b));
      else
        return 2.0 * D_m / (v1 + v2);
    }

getInverseVelocity()

virtual double JACOUSTICS::JSoundVelocity::getInverseVelocity ( const double D_m, const double z1, const double z2 ) const

inlineoverridevirtual

Get inverse velocity of sound.

The inverse velocity is obtained from the propagation time given by method JSoundVelocity::getTime.
Note that the depth is relative to the seabed.

Parameters

D_m	distance [m]
z1	depth [m]
z2	depth [m]

Returns

inverse velocity [s/m]

Implements JACOUSTICS::JAbstractSoundVelocity.

Definition at line 175 of file JSoundVelocity.hh.

    {
      const double eps = 1.0e-8;
 
      const double ct  = (z2 - z1) / D_m;
      const double v1  = (*this)(z1);
      const double v2  = (*this)(z2);
 
      if (fabs(ct) > eps)
        return fabs(log(v2/v1) / ((z2 - z1) * b));
      else
        return 2.0 / (v1 + v2);
    }

Friends And Related Symbol Documentation

operator>>

std::istream & operator>> ( std::istream & in, JSoundVelocity & velocity )

friend

Read sound velocity from input.

Parameters

in	input stream
velocity	sound velocity

Returns

input stream

Definition at line 199 of file JSoundVelocity.hh.

    {
      using namespace JPP;
 
      JStringStream is(in);
 
      if (getFileStatus(is.str().c_str())) {
        is.load();
      }
 
      if (is >> velocity.a) {
 
        is >> velocity.b
           >> velocity.z0;
 
        is.clear();
      }
 
      return in;
    }

operator<<

std::ostream & operator<< ( std::ostream & out, const JSoundVelocity & velocity )

friend

Write sound velocity to output.

Parameters

out	output stream
velocity	sound velocity

Returns

output stream

Definition at line 228 of file JSoundVelocity.hh.

    {
      out << velocity.a << ' ' << velocity.b << ' ' << velocity.z0;
 
      return out;
    }

Member Data Documentation

a

double JACOUSTICS::JSoundVelocity::a

private

Definition at line 236 of file JSoundVelocity.hh.

b

double JACOUSTICS::JSoundVelocity::b

private

Definition at line 237 of file JSoundVelocity.hh.

z0

double JACOUSTICS::JSoundVelocity::z0

private

Definition at line 238 of file JSoundVelocity.hh.

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The documentation for this struct was generated from the following file:

• JSoundVelocity.hh