Introduction to Acoustics

1048 Part H Engineering Acoustics
Part H 24
Table 24.9 Recommended values for some physical quantities in (24.A1)–(24.B5) (ANSI S1.15: 2005)
Environmental Density of Speed of Ratio of Viscosity of Thermal
conditions air ρ (kg/m 3 ) sound c (m/s) specific air η diffusivity
heats γ (Pa s) of air αt (m 2 /s)
T = 23 ◦ C
ps = 101325 Pa 1.1859997 345.677519 1.39836198 1.841268 × 10 −5 2.105344 × 10 −5
H = 50%
Table 24.10 Recommended reference values applicable to dry air at 0 ◦ C and 101.325 kPa. (ANSI S1.15: 2005)
Environmental Density of Speed of Ratio of Viscosity of Thermal
conditions air ρ (kg/m 3 ) sound c (m/s) specific air η diffusivity
heats γ (Pa s) of air αt (m 2 /s)
T = 0 ◦ C
p0 = 101325 Pa 1.29296 331.28 1.3998 1.7268 × 10 −5 1.8123 × 10 −5
conditions. The values in Table 24.9 are shown with
more decimals than necessary and are intended for testing
computation programs that are used to calculate
these quantities.
References
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the recommended values for dry air.
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