1. The problem statement, all variables and given/known data I was trying to validate a calculation I didusing ANSYS fluent, it's about a flow of water that enters a tube, the tube is 16m long and is being heated with a Heat Flux of q'=1077328,47 [W/m^2], now after the simulation runs and I check the results I find out that the steam quality at the exit of the tube is around 69% and not higher, and I need to get a higher quality steam, around 80%. the mass flow is m'=0,5509 [kg/s] the radius of the volume is R=0,01905 m Length L=16m Water enters at: T=20[°C] velocity of entrance is: V=0,484 [m/s] Pressure: P=2000 [psi] or 1,379e+7 [Pa] Tast= 335,472°C I have all the thermodinamics properties of the water at 20 °C, 180 °C, 320°C, 340°C and the saturated temperature 335,472°C Now I ask because I know I'm getting the heat flux wrong but, as far as I knew, when studing Forced Internal Convection it is a good way to get into the problem using the properties at intermedium temperature to find the heat flow and heat flux, and that's why I used the propierties of water of 180°C, but, I know that the properties between 180°C and 320°C are way to different, the especific heat is almost 1,5 times higer and between 320°C and 335,472°C the specific heat increases more than 10%. So, how can I get a more real approximation? Obviusly I can't go and use the Cp at 335.472°C and I need one Cp that allow me to find a representative Heat flow Q' to get a more representative heat flux. What other things I need to considerate? I know that Reynold's number grows too high when I choose a viscocity of higher temperature and it causes Nusselt's number grow, and in consecuence it increases the convection factor h. 2. Relevant equations Heat Flow: Q'=m'*Cp*ΔT Q'=As*h*ΔT Heat Flux: q'=h*ΔT Reynold's number Re=V*D/μ Nusselt's number (A big long eq that depends of Prandtl, Reynold and friction factor) Nusselt's Number Nu= h*D/k 3. The attempt at a solution I was thinkg in doing tables on excel and repeat the calculations to differents lenghts (everything depending on lenght), the thing is, it's a long work, I will have to find many times the different properties of water and do some average to find the heat flux and I just need and approximation to find, validate and confirm the steam quality X=100%. Thanks for the time!