The default Dynamic viscosity (SI unit: Pa·s) is taken From material. Select User defined to enter a different value or expression. The default is 2·10 5 Pa·s.

A M B I E N T C O N D I T I O N S

Enter an Ambient pressure pA (SI unit: Pa). The default is 100 Pa.

G A P P R O P E R T I E S

Enter an Initial film thickness h0 (SI unit: m). Select an option for each of the following:

•Tangential velocity of solid wall ut,w (SI unit: m/s) list—Off (the default), Calculate from deformation, or User defined. If User defined is selected, enter values or

expressions in the matrix.

•Displacement of channel base xb (SI unit: m)—Off (the default) or select User defined to enter different values or expressions in the matrix.

•Tangential velocity of channel base ut,b (SI unit: m/s)—Off (the default), Calculate from deformation, or User defined. If User defined is selected, enter values or

expressions in the matrix.

R A R E F A C T I O N E F F E C T S

The default Relative flow rate function Qch is Slip. Other options are No slip, Model 1,

Model 2, or select User defined to enter a value or expression according to the equations in Relative Flow Rate.

Border

Use the Border feature to set the pressure condition at the border and the border flow type.

B O U N D A R Y, E D G E , O R P O I N T S E L E C T I O N

From the Selection list, choose the geometric entity (boundaries, edges, or points) to define the border. The default setting is to include all geometric entities in the model.

B O R D E R S E T T I N G S

Select a Border condition—Zero pressure (the default), Pressure, or Border flow.

If Pressure is selected, enter a Pressure pf,0 (SI unit: Pa) to define pf pf,0 on the edge, boundary or point. The default is 0.

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