TOOLED THICK COMPOSITES by ARVEN H. SAUNDERS III ...

length CVs for an even number of CVs within a contact area. Correct Pmax to be calculated
later to replace these values.
7. For each CV with holder resin pressure assigned, determine Pappl and resin pressure
based on CV’s current ESS and VF. This resin pressure value to be target average resin
pressure to be calculated for all contacted CVs within each contact area. Note: if all CVs are
contacted then AllContact (Boolean) is true, and all these CVs are treated as a single
contact area.
8. Determine Pmax for each contact area - set Pmax for only laminate top surface j=n+1 CVs.
Then set all other j level CVs to top level values.
9. At this point all CV resin pressure should be defined—Pmax for mid-contact area CVs, 0 for
edges of each contact area, and “” i.e., unknown, for in-between CVs. Submit these values
to Kirchoff algorithm for solution: determine resin pressure for all CVs based on flow that
results in equilibrium pressure drops and resin pressure for the flow resistance network.
10. Determine resin flow volume rates for each CV (cu meters/sec).
11. Determine flow direction for each CV. Alert through display any detected changes in resin
direction.
12. Determine temperature distribution, and update degree of cure, resin viscosity for each CV.
13. Update time + continue. Update each CV status.
3.24 Cure Kinetics Models
The cure kinetics model used for the 3501-6 material is the nth order formulation:
dα
=
dt
where α is cure, A is the pre-exponential factor, Ea is the activation energy, R is the universal
gas constant, T is absolute temperature, and NC is the order. The cure model used for the 8552
material is the autocatalytic formulation:
dα
=
dt
A
n
e
−E
Ae
a
−
RT
48
E a
RT
( 1−
α)
( 1−
α)
NC
NC
( α)
NC 2