Fig. 5
From: Effect of cartilaginous rings in tracheal flow with stenosis
Reynold stresses upstream of the contraction (normalized by the maximum local velocity). The standard error of the Reynolds stresses is calculated as S.E. (u’2/U2) = (u’2/U2)/√(2 N - 2); with N = 1500. This gives a value of about or 1.8%, which is two orders of magnitude smaller than the values at the peak, making even small differences statistically significant