[Vincenzo_]

I'm simulating evaporation through a pipe. Water is flowing inside it and it gets heated with certain heat flux (1077328 W/m^2). It's subcooled water, it enters at 20°C and 2000 PSI, over a 16 m leght it must evaporate around 80% of the fluid. The thing is, I do get the fraction correct, around 80% but when I plot the temperature of the liquid to check the leght when starts the evaporation I found that the temperature of the liquid along the leght keeps rising! it gets more than 1000 K which is impossible since all the energy is used to change the phase and not to increase the temperature.

So, what's happening? Did I miss something to configurate? Is a flaw in the model?

My boundaries conditions are:
Pressure based
2D symmetrical
Turbulent k-epsilon
Water liquid (propierties are piecewise linear to get more close to real values, beacuase water at 320°C has a Cp over 6400 J/kg K)
Water vapor (properties remains constant)
steel (properties constant)

Inlet:
velocity
Liquid V=0,484 m/s T=293K
Vapor V=0, Fraction=0

Outlet:
Pressure
Gauge pressure= 0
Backflow Temperature=335,472 °C (Saturation temperature)
Vapor Blackflow =0

Wall Heated:
Wall
Thermal q=1077328 W/m^2

Axis:
Axis

Operating conditions:
2000 psi

Phase 1: Liquid
Phase 2: Vapor

Interaction: evaporation condensation
Frequency 0.1
Saturation temp: 335,472 °C

Everything else is default.

So what i'm doing wrong? I'm missing something? can someone help?

Thanks for your time!

[Large Epic Simulations]

I would say that this effect would depend on the fluid properties and the vaporization model you're using. I suggest you to check in the theory manual the equations you're using.

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