I have forgotten

• http://facebook.com/
• https://www.google.com/accounts/o8/id
• https://me.yahoo.com
COST (GBP) 0.75 0.00 0

# energy

Computes the total energy radiated by a body with given parameters.
Controller: CodeCogs Contents C++
Excel

## Energy

 doubleenergy( double T double e = 1.0 )[inline]
This module calculates the total energy radiated by a body per unit surface area in unit time.

The total radiative energy of a black body is given by the Stefan-Boltzmann law where is the radiative intensity of the black body.

In practice, the following formula due to Kirchoff is used where is the emissivity constant of the black body , is the emissivity factor of the body and is its absolute temperature.

### Example 1

The following example calculates the total radiative energy emitted by the Wolfram filament of an incandescent light bulb at 3573.16 degrees Kelvin.
#include <codecogs/engineering/heat_transfer/radiation/energy.h>
#include <stdio.h>

int main()
{
// the temperature of the Wolfram filament
double T = 3573.16;

// emissivity factor of the filament
double e = 0.39;

// display the total radiative energy
printf("Energy = %.5lf kW per sq. meter\n",

return 0;
}

### Output

Energy = 3603.96794 kW per sq. meter

### Note

A table with the emissivity factors of various materials at different temperatures can be found at the following link http://www.monarchserver.com/TableofEmissivity.pdf

### References

Dan Stefanescu, Mircea Marinescu - "Termotehnica"

### Parameters

 T the absolute temperature of the body (Kelvin) e Default value = 1.0

### Returns

the total radiative energy emitted by the body (Watt per square meter)

### Authors

Grigore Bentea, Lucian Bentea (November 2006)
##### Source Code

Source code is available when you buy a Commercial licence.

Not a member, then Register with CodeCogs. Already a Member, then Login.