  A second derivative-based moment method is proposed for describing the
thickness and shape of the region where viscous forces are dominant in
turbulent boundary layer flows. Rather than the fixed location sublayer model
presently employed, the new method defines thickness and shape parameters that
are experimentally accessible without differentiation. It is shown
theoretically that one of the new length parameters used as a scaling parameter
is also a similarity parameter for the velocity profile. In fact, we show that
this new length scale parameter removes one of the theoretical inconsistencies
present in the traditional Prandtl Plus scaling's. Furthermore, the new length
parameter and the Prandtl Plus scaling parameters perform identically when
operating on experimental datasets if the Rotta similarity constraint
(u_tau/u_e = constant) holds. This means that many of the past successes
ascribed to the Prandtl Plus scaling also apply to the new parameter set but
without one of the theoretical inconsistencies. Examples are offered to show
how the new description method is useful in exploring the actual physics of the
boundary layer.
