Instruction - Fluent settings and results

Import the mesh and check.

Open Fluent 6.3.26 -> 2ddp (this is a 2 dimensional problem, away choose double precision if memory allows, dp needs more memory but more accurate) ->File->Case->Select File to the Gambit generated mesh file *.msh (in the movie it is wave_chn.msh)->OK->Grid->Check (we need to know if Fluent is happy with the mesh generated by Gambit)->Grid->Scale->here we don¡¯t want to change the scale, so just Close ->

Define the model and BCs, etc.

Define->Solver: Pressure Based (here we solve a incompressible flow problem), Space: 2D; Velocity Formulation: Relative (here you can choose either Absolute or Relative)->Gradient Option: Green-Gauss Node Based (which is more accurate); Formulation: Implicit; Time:Steady.->OK->Define->Model->Vicous->k-epsilon(2 eqn)->in Viscous Model panel, k-epsilon Model:Standard->Near¨CWall Treatment: Enhanced Wall Treatment->keep other parameters unchanged->OK.

->Define->Materials->Density(kg/m3):1; Viscosity(kg/m-s):0.0001(for an appropriate Reynolds number); keep other parameters unchanged->Define->Operating Condition: Operating Pressure(Pascal):0, keep the other parameters unchanged->OK->Define->Boundary conditions, check all the BCs are setup correctly, if not you can change the BCs here -> Define->Periodic Conditions->choose Specify Mass Flow; Mass Flow Rate (kg/s):0.816; keep other parameter unchanged->OK

Define the numerical schemes, etc

Solve->Control->Solution->in Solution Controls panel, Discretization sub-panel: Pressure:PRESTO! ; Momentum: QUICK(3^rd order accuracy, it is always recommended to use higher order scheme); Turbulent Kinetic Energy: QUICk; Turbulent Dissipation Rate: QUICK. In Under-Relaxation Factors, Turbulent Kinetic Energy:0.9; Turbulent Dissipation Rate:0.9; keep other parameters unchanged->OK.

Define the initial condition.

Solve->initialize->initialize->X Velocity (m/s):0.816; Turbulent Kinetic Energy(m2/s2)->0.1->Apply->Init.

Define the solution Monitors.

Solve->Montors->Residual->Residual Monitors->set all the Criteria to 0.0001 (it is ideal to converge at 10^(-6) for your latter work, but sometimes it might be hard).

Create location for monitoring, post-processing etc.

Surface->Line/Rake Surface->Type:Line; x0(m):0.25, x1(m):0.25; y0(m):-0.1, y1(m):1; New Surface Name: x=0.25; -> Create->to create another line, similarly, x0(m):0.75, x1(m):0.75; y0(m):-0.1, y1(m):1; New Surface Name: x=0.75->Create.

Define more solution Monitors.

Solve->Monitors->Surface->in Surface Monitors panel, increase Surface Monitors to 2->click the Plot & Print & Write for monitor-1 & monitor-2->click the Define button of the monitor-1-> in Define Surface Monitor panel, highlight x=0.25 in the Surfaces; Report of: Velocity; subsequently X Velocity; Report Type: Area-Weighted Average; X Axis: Iteration; Plot Window:-1; File Name:x025.out->OK->repeat similarly for moniter-2 for x=0.75->OK

Run the job in the GUI (Graphic User Interface).

Solve->Iterate (you must Initialize the solution, otherwise the Iteration button fades out) ->in Iterate panel, Number of Iteration:1000->Iterate -> You will have 3 Monitors pop out, the Residual, the X Velocity at x=0.25, the X Velocity at x=0.75.

Updated: 07-Oct-2008