Quadratic Stress Law:

1
Quadratic Stress Law
u ? u u, v, w are of similar
magnitude
Can use the Law of the Wall to examine Cd
2
Under HSF Under HRF
3
Typical drag coefficient values
Example of variability
4
Sternberg - Comprehensive study in Puget
Sound Solved for C100 Results 1. C100
varied between two regions of flow (HRF and HTF
to HSF). 2. In HTF too much variability in C100
to be able to use this method, but in HRF, C100
approaches a single value 3. Variability of the
mean as large as the variability at any single
location - Acceptable value C100 3.1 x 10-3
(range 2-4 x 10-3)