Childs Model
The Childs model is based on Hirs’ lubrication equation that includes the effect of fluid inertia in the momentum equation. Expressions are obtained for a short seal theory. The dynamic coefficients for this model are given by
where
The friction loss factor,
λ
, in this model is defined as
The axial and circumferential Reynolds numbers are defined as
and
b
is the ratio of axial to circumferential Reynolds numbers. Other variables in the dynamic coefficient expressions are defined as
