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rrsigma

Compute relative density ratio

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    Syntax

    s = rrsigma(rho,mach,g)

    Description

    s = rrsigma(rho,mach,g) computes the relative density ratio s, from the static densities rho, Mach numbers, mach, and specific heat ratios, g.

    example

    Examples

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    Open Live Script

    Determine the relative density ratio for three densities.

    sigma = rrsigma([1.225 0.3639 0.0953], 0.5, 1.4)
    sigma = 1×3

    1.1297    0.3356    0.0879
    Open Live Script

    Determine the relative density ratio for three densities and three different heat ratios.

    sigma = rrsigma([1.225 0.3639 0.0953], 0.5, [1.4 1.35 1.4])
    sigma = 1×3

    1.1297    0.3357    0.0879
    Open Live Script

    This example shows how to determine the relative density ratio for three densities at three different conditions.

    sigma = rrsigma([1.225 0.3639 0.0953], [0.5 1 2], [1.4 1.35 1.4])
    sigma = 1×3

    1.1297    0.4709    0.3382

    Input Arguments

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    M static densities, specified as a scalar or vector in kilograms per meter cubed.

    Example: [1.225 0.3639 0.0953]

    Data Types: double

    M mach numbers, specified as a scalar or vector.

    Example: [0.5 1 2]

    Data Types: double

    M specific heat ratios, specified as a scalar or vector.

    Example: [1.4 1.35 1.4]

    Data Types: double

    Output Arguments

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    M density relative ratios, returned as a scalar or vector.

    Limitations

    For cases in which total density ratio is desired (Mach number is nonzero), the total density is calculated assuming perfect gas (with constant molecular weight, constant pressure specific heat, and constant specific heat ratio) and dry air.

    References

    [1] Pratt & Whitney Aircraft. Aeronautical Vestpocket Handbook. United Technologies, August 1986.

    Version History

    Introduced in R2006b

    See Also

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