How to define Inlet air with relative humidity in CFX for turbo machinery?

manupanand · January 4, 2023, 21:17

How can I define relative humidity of air in CFX , I want to calculate the condensation in compressor/ evaporation due to humidity. How to define the air with relative humidity?

How to define the material with air+water content?

ghorrocks · January 5, 2023, 16:37

If there is no condensation then it is usually modelled as a multicomponent mixture. You model dry air + water vapour. You can then define equations to get the relative humidity from the mass fractions.

If the water condenses and you have mist forming, or water droplets on walls or anything like that it is significantly more complex and you will need the multicomponent mixture and a multiphase model. This type of model will require a skillful CFD operator to complete and is definitely not for beginners.

manupanand · January 6, 2023, 02:52

Thank you.Can you share any documents for doing simulation without condensation

January 4, 2023, 21:17	How to define Inlet air with relative humidity in CFX for turbo machinery?	#1
manupanand Member MANU P ANAND Join Date: Jul 2014 Location: Daegu , REPUBLIC OF KOREA Posts: 36 Rep Power: 11	How can I define relative humidity of air in CFX , I want to calculate the condensation in compressor/ evaporation due to humidity. How to define the air with relative humidity? How to define the material with air+water content?

January 5, 2023, 16:37		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	If there is no condensation then it is usually modelled as a multicomponent mixture. You model dry air + water vapour. You can then define equations to get the relative humidity from the mass fractions. If the water condenses and you have mist forming, or water droplets on walls or anything like that it is significantly more complex and you will need the multicomponent mixture and a multiphase model. This type of model will require a skillful CFD operator to complete and is definitely not for beginners. Opaque and manupanand like this. __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

January 6, 2023, 02:52		#3
manupanand Member MANU P ANAND Join Date: Jul 2014 Location: Daegu , REPUBLIC OF KOREA Posts: 36 Rep Power: 11	Thank you.Can you share any documents for doing simulation without condensation Last edited by manupanand; January 12, 2023 at 18:47.

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