1 2 3 4 5 6 7

52) Go to Limiting Values for Field Variables and activate K and E by checking the corresponding checkboxes, then enter the values as shown in Fig.4.0. Click Apply.

Fig - 4.0: Dialog box for Limiting values.

53) click "Solution Method for Built-in Matrix". Screen will be like as shown in fig 4.1

Fig - 4.1: Dialog box for Matrix Solver.

1. We will have matrix sweeps only in X and Y directions, so check Solution Methods for Individual Variables. Keep X, Y as Checked and Z as unchecked.
2. Check the checkbox for P, enter 6 as Number of Sweeps, leave Alternating Direction Implicit (ADI) method selected, as shown in Fig.4.1
3. Click "Apply".

54) Now click "Relaxation factor" on Advanced Output Control Option window.

1. We would like to have Relaxation Factors of 0.3 for U, V, K and E; and 0.6 for P.. By default the relaxation factor for all active variables is 0.5. The only exception is P (pressure) and that of P is 1.0. Hence we will change the relaxation factor of P, U, V, K and E as shown in figure 4.2.



fig - 4.2: Dialog Box for relaxation Factor

2. Click "Apply"

55) Click "Close" on Advanced Output Control Option window to terminate the window.

56) Click "Next >" to go to Runtime Control dialog window. (See Fig 4.3)

Fig - 4.3: Runtime Control dialog window

57) Click "Solve >>" and dialog box appears as seen in Fig 4.4.

Fig - 4.4: Steady State dialog box

 Specify the values as follows

1. Select Customize "SOLVE" Command Options.
2. Specify Maximum and minimum number of steps as 1500 both, for fixed number of steps.
3. Click "Apply".

58) Click "Finish" and a message window appears as shown in fig 4.5. Click "Yes" to save the project.

Fig 4.5 Answer Message window

This concludes the setup of the problem. If it is not already, make the Commands File viewable. It should look like:

/==== PROBLEM IDENTIFICATION ====/ TITLe FlowPastTwoCylinders USER TutorialUser /==== GEOMETRY SPECIFICATIONS ====/ GRID 100 by 60 COORdinates X Y BLOCk format 1 header line file = 'FlowPastTwoCylinders.grd' LOCAte ID=CYL1 LIST 1206 1207 1208 1209 1304 1305 1306 1307 1402 1403 1404 1405 1500 1501 1502 1503 1598 1599 1600 1601 LOCAte ID=CYL2 LIST 4048 4049 4050 4051 4146 4147 4148 4149 4244 4245 4246 4247 4342 4343 4344 4345 4440 4441 4442 4443 /==== INITIAL & BOUNDARY CONDITIONS ====/ INLEt at X- boundary OUTLet at X+ ;1.0 WALL at everywhere unless otherwise specified BLOCkage at ID=CYL1 BLOCkage at ID=CYL2 SET U everywhere 1.0 SET V everywhere 0.0 SET P everywhere 0.0 SET K everywhere 0.01 SET E everywhere 0.111 BOUNdary condition U VALUe X- 1.0 BOUNdary condition K VALUe X- 0.01 /==== FLUID PROPERTIES & CONSTANTS ====/ DENSity of FIRSt phase =1.0 VISCosity of fluid FIRSt phase 1.53E-03 /==== NATURE OF FLOW ====/ TURBulent model HRe Ke /==== SOLUTION OPTIONS ====/ LIMIT value of K; min: 1.0e-7; max: 1.0e+7 LIMIT value of E; min: 1.0e-7; max: 1.0e+7 MATRix Sweep in Direction(s) X Y MATRix P sweep 6 times using method: ADI RELAxation Factor; U=0.3;V=0.3;P=0.6;K=0.3;E=0.3; /==== OUTPUT CONTROL ====/ SAVE U V P K E 'FlowPastTwoCylinders.sav' FORMatted DIAGnostic node at (60,35) frequency :(1) U RU V RV P K E CONVergence U GLOBal 1.0E-6 1 phase /==== RUNTIME CONTROL ====/ SOLVe STEADy-state Nmax=1500 ,Nmin = 1500 END

Fig - 4.6: Command file.

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