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Thermal Conductivity of gas mixture

Thermal Conductivity of gas mixture

Thermal Conductivity of gas mixture

(OP)
Hi, can someone direct me to a book, or website, whcih can show me how to calculate thermal conductivity and dynamic viscosity of mixture of gases?

My mixture consists of: Hydrogen, Nitrogen, Carbon monoxyde, Carbon Dyoxide, Methane and water vapor...

I need formula to calculate thermal conductivity, and viscosity..

Thank you for help in advance.
 

RE: Thermal Conductivity of gas mixture

Ercegs,

There are procedures in the TEMA (Tubular Exchanger Manufacturers Association) book for calculating the properties of mixed gases.  However, you need the individual properties to do it.

Regards,

speco

RE: Thermal Conductivity of gas mixture

I suggest Perry-Chilton 'Chemical Engineers' Handbook', if you can have access to it: it has a long chapter entirely devoted to chemical and physical properties and to the prediction and correlation of physical properties.
In short, if you don't need a detailed discussion and references, this is what they suggest for gas mixtures at low pressures.
-thermal conductivity kyiki(Mi)1/3yi(Mi)1/3
-viscosity μyiμi(Mi)1/2yi(Mi)1/2
where y is the mole fraction and M the molecular weight.

prex
http://www.xcalcs.com : Online engineering calculations
http://www.megamag.it : Magnetic brakes for fun rides
http://www.levitans.com : Air bearing pads

RE: Thermal Conductivity of gas mixture

(OP)
Speco,

thank you very much...And can you tell me, for water vapor, I need cp, thermal conductivity etc...On the net, I have only found values for 1 bar, and I have 21 bar at 210deg celsius?

Is it possible to find somewhere these values, or these values are available only for 1 bar?

RE: Thermal Conductivity of gas mixture


Pay a visit to the site suggested by iainuts. You"ll find that water at 210oC and 21 bar is a liquid.
 

RE: Thermal Conductivity of gas mixture

(OP)
Yes, I saw that..but, someone is trying to convince me that Cp for water vapor at 210deg and 21 bar is 1.97kj/kgK (and that is the value for 210deg and 1 bar)...So I just wanted to see if I'm right

RE: Thermal Conductivity of gas mixture

Cp for water vapor is;I understand is at contant pressure.Thus Cp must vary with changed pressure conditions.
The Change of phase case involves absorbtion of(Latent)heat when boiling starts around atmospheric pressure.
Hope this is helping

Best Regards
Qalander(Chem)

RE: Thermal Conductivity of gas mixture


At 21 bar and 215oC, the vapor Cp = 3.23 kJ/(kg.K), from the NIST table.

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