(U.S. Naval Academy (USNA), EW-9-90, *Evaluation of Viscous Damping Models for*

Equation 11 provides a reasonable estimate of drag coefficients. Predicted current

forces for this example are given in Table 4-6.

d

d

Fyc

Fyc

T/d

(m)

(ft)

(MN)*

(kips)**

0.096

45.7

150

0.55

123

0.288

15.2

50

0.66

148

0.576

7.62

25

1.03

231

0.72

6.096

20

1.30

293

0.96

4.572

15

1.90

427

* MN = one million newtons

**kip = one thousand pounds force

This example shows that in shallow water the transverse current force can be three

times or larger than in deep water for an FFG-7.

87