[Taron]

Hi to all!
I am doing simulation of vapor condensation by ANSYS CFX 17.2 . My model consists of 3 differnet domains:
1. Tube
2. Tube's steam
3. Water Tank in which Tube is submerged

Through inlet it is enters steam with pressure 70bar and temperature 280C.
As Tube is submerged in water tank, which have constant 30C degree temperature, flowing steam must condensed. However this is the theory that I must get in CFX-post.

So I already enabled Physics Beta Features, as there must be different materials in different domains. But modeling multiphase flow in tube's steam domain I am having error: " There must be an object of type "MASS TRANSFER" in the object "/FLOW:Condensation Analysis/DOMAIN:Tubes Water/FLUID PAIR:Liquid | Vapor" but it does not exist.

Could anyone say whats my problem, what object does the program wants?

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[ghorrocks]

It is unusual to model this sort of thing as multiple domains. The normal approach is to use a single domain and a multiphase model.

Why are you doing it using separate domains?

[Taron]

I use separate domains for having opportunity to give different parameters(pressure, temperature,different materials).

[Opaque]

You cannot have different materials between fluid domains that are connected. You can have a multicomponent mixture, or a multiphase mixture for all the connected domains.

It may be the mass fraction, or volume fraction of a given material is 0 in a given domain, but it must be defined for all the domains.

[Taron]

Sorry for late answer Opaque, but fluid domains in my model aren't connected, I mean they do not mix at all( there is solid domain: tube,,, between them).
Their physical parameters are fully different. Look at the attached photo.

[Opaque]

Got it.. Thank you for the snapshot.

Create domain Tubes Steam, insert a single fluid, say Fluid1, and assign material Steam (for example).

Create domain TankWater, insert a single fluid, say Fluid2, and assign material Water,

Create domain TubeSolid, insert a solid, say Solid 1, and assign material appropriate for the tube.

Now you got a single phase flow heat exchanger model. I would run this case to get familiar with any issues of running a beta feature such as non-constant domain physics. Once you are successful with the above you may want to increase the level of complexity if needed.

Good luck, and keep us posted.

[Taron]

Thank you. Having ready results I will get in touch.