[anon_l]

Hi all,
I am trying to run a simulation with supercritical H2O through a simple tube geometry with thickness (conjugate heat transfer).
Steps-
1)created geometry in star ccm CAD for the fluid body and defining its region with the boundaries inlet , inner wall and outlet
2)Then used extrusion to generate the solid geometry and region from the fluid using the mesh conditions at the inner wall.
3) physics for both fluid and solid regions created
4)line probes and planes created for visualization of the solution
My aim-
1)use a volumetric heat source at the outer wall of the tube as a heat source .
2)inlet h20 temp = 35.4 degree C , outlet temp = 356 degree C
3)mass flow= 587.6 gm/m^2-s
4) heat power = heat flux at inner surface of tube = 0.623 MW/m^2
5)outer surface of the tube is considered adiabatic .
6)pressure = 25 MPA
I want to make a temperature profile curve of the outer surface of the tube . However , I do not get proper results . I also don't get any value for the heat transfer coefficient .

My main problem is what boundary conditions and inital conditions should I choose for each region . Should I put heat flux at the inner wall of my fluid region or the inner wall_extrusion base of my extruded solid region or at the interface ?

Pictures of my mesh and physics conditions and regions are also included.


Thanks

[anon_l]

Since I use supercritical H20 , I use the following functions for the properties-

density
Number of interval
3
Interval ranges
[663,700, 800, 1073]
Numbers of coefficients
[5,5,4]
Coefficient
[20888437.32897, -121466.279457929, 264.892650225018, -0.2567597311521, 0.000093333082540744, 79195.9972248006, -404.619712014594, 0.7784131025619, -0.00066713291581415, 2.1477224361164E-07, 902.76678358608, -2.2681931455009, 0.002078145302, -6.5474813334491E-07]
Exponents
[0.0,1.0,2.0,3.0,4.0, 0.0,1.0,2.0,3.0,4.0, 0.0,1.0,2.0,3.0]
--------------------------------------------------------------------------------
Specific heat
Number of interval
3
Interval ranges
[663,683,783, 1073]
Numbers of coefficients
[5,5,5]
Coefficient
[72098255169.205, -426901983.90771, 947913.913893974, -935.475678541713, 0.3462040914552, 35740652.493319, -189447.825833259, 376.86407580743, -0.3333750897413, 0.00011063602503477, 223117.120300903, -870.188643358111, 1.2944485418665, -0.00085908519886809, 2.1442187362133E-07]
Exponents
[0.0, 1.0, 2.0, 3.0, 4.0, 0.0, 1.0, 2.0, 3.0, 4.0, 0.0, 1.0, 2.0, 3.0, 4.0]
----------------------------------------------------------------------------------------------------------------------
Dynamic viscosity
($Temperature<663.0)? 3.15716e-5:
(($Temperature<683.0)? 6.9224264624736-0.0408832952645*$Temperature +0.000090549079244015* pow($Temperature,2)-8.913669797436E-08* pow($Temperature,3)+3.2906108603975E-11* pow($Temperature,4):
(($Temperature<783.0)? 0.0108989512696-0.000057839685831513*$Temperature +1.1532390544032E-07* pow($Temperature,2)-1.0216997356426E-10* pow($Temperature,3)+3.3955858119227E-14* pow($Temperature,4):
(($Temperature<1073.0)? -0.0000032427270621927+4.741942361337E-08*$Temperature +-4.78555217991E-12* pow($Temperature,2): 4.21E-5)))
-------------------------------------------------------------------------------------------------------------------------
Thermal conductivity
($Temperature<663.0)? 0.2264:
(($Temperature<695.0)? 47661.033038555-278.416789654012*$Temperature +0.6099315425136* pow($Temperature,2)-0.00059388587645495* pow($Temperature,3)+2.1685650279812E-07* pow($Temperature,4)
:
(($Temperature<775.0)? 185.834410219319-0.9793944425447*$Temperature +0.0019389248748* pow($Temperature,2)-0.0000017078378939546* pow($Temperature,3)+5.6465757723963E-10* pow($Temperature,4):
(($Temperature<1073.0)? 2.4199512766181-0.0094779285294*$Temperature +0.000014350317833471* pow($Temperature,2)-9.5997271574745E-09* pow($Temperature,3)+2.421812079001E-12* pow($Temperature,4): 0.123)))
------------------------------------------------------------------------------------------------------------------------
Prantl Number
($Temperature<663.0)? 3.9489:
(($Temperature<700.0)? 712655.370282141-4137.78650804068*$Temperature +9.0095886619281* pow($Temperature,2)-0.0087191263008* pow($Temperature,3)+0.0000031643427014962* pow($Temperature,4):
(($Temperature<800.0)? 1789.0113166512-9.1712038684109*$Temperature +0.017667884118* pow($Temperature,2) -0.00001514546110914* pow($Temperature,3)+4.8732160696751E-09* pow($Temperature,4):
(($Temperature<1073.0)? 35.1933611129059-0.132228857307*$Temperature +0.00019253019932984* pow($Temperature,2)-1.2511500694886E-07* pow($Temperature,3)+3.0554723673796E-11* pow($Temperature,4): 0.91)))

[wassli]

I just wonna know that are you using Coupled Solver or Segregated Solver ?

[anon_l]

@wassli , I used segregated .

[wassli]

i am also using Segregated solver and get accurate results but unable to get results in coupled solver, so that's why i asked for.