I think I found it.
int IfmSetBcFlowTypeAndValueAtCurrentTime
(
IfmDocument pDoc,
int nNode,
[b]int bcType,[/b]
int bcUnst,
double nValue
);
int bcType
Flow B.C. Type:
[b]IfmBC_NONE (0) = no boundary condition [/b]
IfmBC_DIRICHLET (1) = Dirichlet (1st kind)
IfmBC_NEUMANN (2) = Neumann (2nd kind)
IfmBC_CAUCHY (3) = Cauchy (3rd kind)
IfmBC_SINGLE_WELL (4) = Single well (4th kind)
IfmBC_GRADIENT_FTYPE (5) = Gradient-type
Note: (a) if IfmBC_NONE is used an existing B.C. Is deleted,
(B) do not use a type larger than IfmBC_GRADIENT_FTYPE.