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Prandtl Number of Air

The prandtl number of air is around 0.7 as many other gases at 1 atm.
The Prandtl Number is a dimensionless number approaching the proportion of momentum diffusivity and thermal diffusivity.
Prandtl number equation is defined as:

Prandtl Number of Air
Prandtl number equation

where:
ν is the kinematic viscosity, ν = μ / ρ.
μ is dynamic viscosity, (SI units: Pa s = N s/m2).
ρ is density, (SI units: kg/m3).
α is the thermal diffusivity, α = k / (ρ cp).
k is thermal conductivity, (SI units: W/m·K)
cp is specific heat, (SI units: J/kg·K)
ρ is density, (SI units: kg/m3).
The values of μ, cp and k are acknowledged to change with temperature consequently the Prandtl number will change with temperature.
The values of μ, cp and k are only very weak functions of pressure so the Prandtl number presumed independent of pressure.

Prandtl Number of Air

Prandtl Number of Dry air at 1 atm pressure:

Temp, CTemp, FTemp, KPrandtl
Number, Pr
-193.15-315.6780mix
-183.15-297.67900.7960
-173.15-279.671000.7860
-153.15-243.671200.7730
-133.15-207.671400.7630
-113.15-171.671600.7540
-93.15-135.671800.7450
-73.15-99.672000.7380
-33.15-27.672400.7240
6.8544.332800.7100
26.8580.333000.7050
76.85170.333500.6990
126.85260.334000.6940
176.85350.334500.6910
226.85440.335000.6890
326.85620.336000.6900
426.85800.337000.6960
526.85980.338000.7050
626.851160.339000.7090
726.851340.3310000.7110
Prandtl number of air Celsius C
Prandtl number of air Celsius C
Prandtl number of air farenheit, F
Prandtl number of air farenheit, F
Prandtl number of air Kelvin K
Prandtl number of air Kelvin K

Note: For ideal gases, the properties cp, k, m, and Pr are independent of pressure.

Prandtl number of air (dry Air) Table at temperature between 70 deg C and 2000 deg C :

Temp, CTemp, FTemp, KPrandtl
Number, Pr
70158343.150.7177
80176353.150.7154
90194363.150.7132
100212373.150.7111
120248393.150.7073
140284413.150.7041
160320433.150.7014
180356453.150.6992
200392473.150.6974
250482523.150.6946
300572573.150.6935
350662623.150.6937
400752673.150.6948
450842723.150.6965
500932773.150.6986
6001112873.150.7037
7001292973.150.7092
80014721073.150.7149
90016521173.150.7206
100018321273.150.7260
150027321773.150.7478
200036322273.150.7539

Note: For ideal gases, the properties cp, k, m, and Pr are independent of pressure.

Prandtl Number of Air @ Different Pressure

Temp, CTemp, F10 bar30 bar50 bar70 bar100 bar
-193.15-315.672.322.372.422.482.57
-183.15-297.671.771.791.821.851.91
-173.15-279.671.541.531.531.531.55
-153.15-243.670.891.651.481.41.34
-133.15-207.670.821.22.142.071.52
-113.15-171.670.780.921.131.371.72
-93.15-135.670.7630.830.9321.071.25
-73.15-99.670.7490.7880.8410.91
-33.15-27.670.7290.7460.7670.80.82
6.8544.330.7130.7210.7310.7420.76
26.8580.330.7080.7150.7210.7280.742
76.85170.330.6990.7030.7070.7110.716
126.85260.330.6940.6960.6980.70.704
176.85350.330.6910.6920.6930.6940.696
226.85440.330.6890.6890.690.690.691
326.85620.330.690.6890.6890.6890.69
426.85800.330.6950.6950.6950.6950.695
526.85980.330.7040.7040.7030.7030.702
626.851160.330.7080.7080.7080.7080.708
726.851340.330.7110.7110.710.710.709
Prandtl Number of Air @ Different Pressure
Prandtl Number of Air @ Different Pressure

Prandtl Number of Air @ Different Temperature

 280 K300K500K1000 K
10.710.7050.6890.711
50.7110.7070.6890.711
100.7130.7080.6890.711
200.7170.7120.6890.711
300.7210.7150.6890.711
400.7260.7170.690.71
500.7310.7210.690.71
600.7370.7250.690.71
700.7420.7280.690.71
800.750.7320.6910.709
900.750.7370.6910.709
1000.760.7420.6910.709
Prandtl Number Of Air at Different Temperature
Prandtl Number Of Air at Different Temperature

Prandtl number of Humid air

Prandtl number of moist air with a relative humidity (RH) varying between 0% and 100%

Prandtl Number of Air
Prandtl number of humid air

References:

Thermophysical and transport properties of humid air at temperature range between 0 and 100 C P.T. Tsilingiris *
https://www.researchgate.net/profile/Ingo_Riess/post/What_should_be_the_viscosity_of_Air_Water_Mixture/attachment/5acb4c45b53d2f63c3c4b633/AS%3A613464624070664%401523272772980/download/2007_Properties+of+humid+air.pdf

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