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On boundary and initial conditions in general
 Boundary conditions are extremely important. They are the most common causes of errors.
 OpenFOAM uses similar setup as other solvers.
 At the inlet (flow inlet) to the computational domain total pressure and total temperature are set. The rest of variables is reconstructed.
 At the outlet the static pressure is set.
 At the rigid walls velocity is set to zero.
 Multiple Reference Frame (MRF) is used for rotational components.
 For steadystate computations the initial conditions have no influence to the results.
 For steadystate computations the initial conditions just help to make the case run.
The main variables to be set are following: static pressure p, velocity vector U, static temperature T, turbulent kinetic energy k and specific turbulence dissipation omega. The initial and boundary conditions for all variables are set in files in directories called by numbers. Typically directory 0 is recommended to start simulation from. Initial conditions are set in parameter initialField, those are cell centers. At boundaries, initial conditions are set individually by parameter value. Following table shows recommended model boundary conditions for computed variables:

The shortcuts from the above table have following meaning:
 tP – totalPressure , constant e.g. 500 000 Pa, gamma = 1.47948 [] is specific heat ratio
 pDIV – pressureDirectedInletVelocity, velocity is computed from difference between total and static pressure, inletDirection is velocity vector to be specified
 tT – totalTemperature, constant e.g. 1050 K, gamma = 1.47948 [] is specific heat ratio
 tIKEI – turbulentIntensityKineticEnergyInlet, intensity = 0.02, corresponds to turbulence intensity 2%
 fV – fixedValue, e.g. velocity at the wall (0 0 0), or omega at inlet
 fMV – fixedMeanValue, is same as fixed value e.g. for pressure, but certain freedom is allowed to keep the variable average equal to meanValue
 zG – zeroGradient, the flux of the variable is zero in direction perpendicular to the surface
 TWF – compressible::turbulentTemperatureCoupledBaffleMixed special boundary condition for temperature enabling heat transfer from other regions
 kWF – compressible::kqRWallFunction is standard wall function for k for compressible flow
 oWF – compressible::omegaWallFunction is standard wall function for omega for compressible flow
 mPV – mixingPlaneVelocity, averaged velocity is mapped from neighbour patch
 mP – mixingPlane, averaged variable is mapped from neighbour patch
 iO – inletOutlet is by default zeroGradient, but change to fixedValue when velocity vector direction aims inside the computational domain (backward flow)
 AMI – cyclicAMI is Arbitrary Mesh Interface boundary condition allowing data interpolation between two patches of different mesh topology.
 cc – calculated, boundary values of a certain quantity is simply calculated, in accordance with its definiton, from values of other quantities that already have prescribed their boundary conditions
Two other variables must be presented for postprocessing purposes: total pressure pTot and total temperature TTot. The boundary conditions for total pressure and total temperature are formal and are always the same
boundaryField { "(.*)" { type zeroGradient; } }
However, there are cyclicAMI patches present and thus boundary condition prescription, although being formal, must obey this fact. Therefore we add a following entry to boundaryField subdict of each file, either the pTot or TTot file.
"(.*_cyc_.*)" { type cyclicAMI; value uniform 0; }
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