Hi,

Does anyone know where I could find values for the sutherland's law coefficients that define the viscosity of Argon (S,Mu0 and T0)?

I have searched the web with google extensivley but cannot find a reference

thanks

Reference Viscosity, Mu0(kg/m-s) = 2.125e-05 Reference Temeprature, T0(K) = 273.11 Effective Temperature, S(K) = 144.4

Hope it helps

Regards

Apurva

Hi Apurva,

Thanks for your response. Would you be able to tell me where this information comes from so that I can reference it in my report.

Thanks.

Michael,

I have used data from two sources: CRC handbook and data in the NIST online database (http://properties.nist.gov/SemiProp/Gases/ar.html ). I then fitted it to Sutherland's law, resulting in

S = 164.2K, Tref = 1000K, MUref = 55.8[microPa-s]

Hi Michael

Mine information comes from Fluent. Actually Fluent has a database of such properties.

Regards

Apurva

Apurva,

Sorry for arguing, but I have put your coefficients in Sutherland's law and plotted it on top of mine and the data points from CRC and NIST. It falls somewhat below the actual viscosity, whereas my fit is closer. You may check it for yourself.

for your convenience, the data is:

p=1bar

source CRC CRC CRC CRC CRC CRC CRC CRC CRC CRC CRC CRC CRC CRC CRC CRC CRC CRC CRC CRC NIST NIST NIST NIST

T[K] 85 90 100 120 140 160 180 200 220 240 260 280 300 320 340 360 380 400 500 600 700 800 900 1000

visc.[uPa-s] 278.8 7.5 8.2 9.8 11.4 13.0 14.5 16.0 17.5 18.9 20.3 21.6 22.9 24.2 25.4 26.6 27.8 28.8 34.2 39.0 43.6 47.9 51.9 55.8

References: CRC handbook '97-'98, pp. 6-18, 6-194, 6-201.

NIST: http://properties.nist.gov/SemiProp/Gases/ar.html

Notes:

o p=1bar

o At T=85K Ar is condensed

o T=1000K is my choice of Tref

Thanks both of you for you help. I worked out the relative difference in the models to be 13% (independent of temperature ofcourse). Either one will work ok for me.

Viscous Fluid Flow by Frank White (McGraw-Hill) provides the numbers for Argon. However, he simply reproduces the numbers from another reference (Hilsenrath, J., et al, Tables of Thermodynamic and Transport Properties, National Bureau of Standards, 1955.)

[estang]

Originally Posted by Rami
;25031

o T=1000K is my choice of Tref

The NIST chemistry webbook only provides data to 700 K to me when i request for isobaric data of Ar at 1 bar. Is your Tref really 1000K?