I need to design a Heat Exchanger which is having the above gas mixture as one of the fluid. I need to find out the above properties. Someone suggest me to refer Perry'S Data Book to find that. But I am not able to find that.
Composition of each gas in mixture is in mole% H2-50, N2-19, Ar-3.66, CH4-8.16,NH3-19 and temperature is 430 degree Celsius.
Hi Sandeep,
The most accurate estimation for those properties and mixture can be obtained using Refprop NIST (http://www.nist.gov/srd/nist23.cfm).
Maria
NIST databases are excellent and easy to use. If you want a methodology for conduction calculations, you can check out:
http://www.egr.msu.edu/classes/me812/somerton/Mixtures.pdf
for viscosity: explanation from the department of interior/bureau of mines is a good reference
http://www.google.ca/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=5&ved=0CDcQFjAE&url=http%3A%2F%2Fstacks.cdc.gov%2Fview%2Fcdc%2F10045%2Fcdc_10045_DS1.pdf&ei=KcaCVenMILTfsAT6oYLQAQ&usg=AFQjCNFVWal-tGr-8lsdzVVmLVXj5gtFwQ
heat capacity: calculate by mole fractions
http://libvolume5.xyz/industrialproductionengineering/btech/semester3/basicthermodynamics/idealgasmixture/idealgasmixturetutorial1.pdf
I believe the Prandtl number is just the combination of the above variables.
Andrew
Thank You.. But in NIST database Hydrogen and ammonia mixture is not possible. Can I konw How to fix this .Any other solution to find these properties analytically ??
Hello Sandeep
The calculation of the mixture heat capacity is pretty simple as long as there are no chemical reactions. To find the heat capacity of the mixture you might add the heat capacity of each component and weight it by its weight or mole fraction according to the desired unit of the result. You'l find a desciption in every good text book on thermodynamics.
Much more difficult is to derive the transport properties of a mixture as conductivity or viscosity.
The best referenc I know is the book "The Properties of Gases and Liquids" by Poling, Prausnitz and O'Connell (McGraw-Hill, New York, 5th ed. 2001, ISBN 0-07-011682-2). I guess that you'll find it in good University libraries or possibliy in the Internet. Chapter 6 is about heat capacity, chapter 9 on viscosities of mixtures, and chapter 10 on thermal conductivity of pure substances and mixtures. In the appendix you 'll find polynoms to numerical derive the properties of the components you listed.
Best regards
Nikolaus
Hello there
The book mentioned by Dr.Nikolaus Hannoschöck is a really great source of methodologies on properties estimation. I have used it in some problems and methods are accurate and useful for cod developing if you are looking for one. But according to your problem, a combination of Nitorgen, Hydrogen, Hydrocarbons and Ammonia, please be very careful to choose the appropriate methods. Since the temperature is high and lies between the Harber Ammonia production equilibrium equation, please make sure that no net reaction occurs during the cooling or heating process. Another issue is the material of the heat exchanger which uses for this mixture handling. As you know some metals like Iron work as Catalyst in Ammonia,Hydrogen and Nitrogen reaction.
Are you designing this heat exchanger for Ammonia or Hydrogen production plant with natural gas feed?
Best Wishes
Hasan
You can find the way to calculate them in our paper:
http://dx.doi.org/10.1088/1742-6596/622/1/012010 .
The following somewhat related discussion ― on Cp/Cv ratio for reacting gases ― may possibly be found interesting by followers of this discussion: https://www.researchgate.net/post/how_can_we_calculate_gamma_specific_heat_ratio_for_real_gas_chemical_non-equili
- Badges
- Science topic