(34)

0 > u > a′.

(35)

Along the jet surface A′J′, q = Q,

ch nΩ = cos nθ = √ b − a′√ a − u,
a − a′ b − u

(36)

sh nΩ = i sin nθ = i √ a − b√ u − a′.
a − a′ b − u

(37)

a′ > u = a′eπ/sc > −∞,

(38)