$LastChangedDate: 27-Juil-2011 $

# CL_man_consumption

Mass consumed as function of delta-V

## Calling Sequence

       [output] = CL_man_consumption(type_output,par1,par2,par3 [,g0])
       [dm] = CL_man_consumption('dm',dv,m,isp[,g0])
       [dv] = CL_man_consumption('dv',dm,m,isp[,g0])
       [m] = CL_man_consumption('m',dm,dv,isp[,g0])
       [isp] = CL_man_consumption('isp',dm,dv,m[,g0])

## Description

- The mass consumed by a maneuver can be computed by the following equation:

  Given 3 of the 4 variables that appear in the equation (mass consumed, norm of velocity increment, Isp or initial mass), the function computes the 4th one.

  The output argument type_output defines the parameter to be computed. It can be one of the following:

  - 'dm': mass consumed

  - 'dv': norm of delta-V

  - 'isp': propellant specific impulse.

  - 'm': initial mass

  Note: The input arguments are always in the same order: dm, dv, m, isp.

## Parameters

type_output:

  String defining the parameter to be computed. It can be 'dm,'dv','m' or 'isp'. (1x1)

par1:

  First input parameter: dm, dv, m or isp [kg m/s kg or s] (1xN)

par2:

  Second input parameter: dv, m or isp [m/s kg or s] (1xN)

par3:

  Third input parameter: m or isp [kg or s] (1xN)

g0:

  (optional) Value of gravity acceleration. [m/s^2] (default value is %CL_g0) (1x1)

output:

  Value of computed parameter: dm, dv, m or isp [kg m/s kg or s] (1xN)

## Authors

- CNES - DCT/SB

## Bibliography

- 1) Orbital Mechanics for Engineering Students, H D Curtis, Chapter 6, equation 6.1

- 2) Mecanique spatiale, CNES - Cepadues 1995, Tome I, section 4.8.6

## See also

- CL_man_thrustDuration

## Examples

    // Compute mass consumed
    isp = 220; // seconds
    dv = 1; // m/s
    m = 180; // kg
    dm = CL_man_consumption('dm',dv,m,isp); // mass consumed in kg

    // Compute delta V
    isp = 220; // seconds
    dm = 1; // kg
    m = 180; // kg
    dv = CL_man_consumption('dv',dm,m,isp); // delta V in m/s

    // Compute initial mass
    isp = 220; // seconds
    dv = 1; // m/s
    dm = 1.8; // kg
    m = CL_man_consumption('m',dm,dv,isp); // initial mass in kg

    // Compute Isp
    dm = 1; // kg
    dv = 1; // m/s
    m = 180; // kg
    isp = CL_man_consumption('isp',dm,dv,m); // isp in sec