Symbol 



6 

 (Theta) 



M 

 (Mu) 



(Nu) 



i 



(Xi) 



n 

 (Pi) 



P 

 (Rho) 



'fw 



a 



(Sigma) 



Definition 



Wave phase angle (Ch. 2) 



#Angle of wind measured counter- 

 clockwise from X axis at shore 



#Angle of structure face rela- 

 tive to horizontal (eq. 7-113; 

 Fig. 7-107) 



• Angle of backslope of retaining 

 wall (eq. 7-142) 



• Angle of side slope with the 

 horizontal in direction of flow 



Coefficient of friction (soil) 



Kinematic viscosity (Ch. 7) 



Atmospheric pressure deficit in 

 head of water (eq. 3-77) 



• Horizontal particle displace- 

 ment from wave passage 



(eq. 2-17) 



• Surf similarity parameter 

 (eq. 2-86) 



Dimension 



Constant = 3.14159 



Mass density = w/g 



• Mass density of water 

 (eq. 4-35) 



Mass density of air 



Mass density of fresh water 

 (1000 kg/m^)^ 



t 



Mass density of armor material 



Mass density of sediment 



Mass density of water (salt water 

 = 10.31 X 10^ kg/m^; fresh water 

 = 1000 kg/m^)^ 



Standard deviation 



• Wave frequency, Zn/T 



Annual standard deviation of sig- 

 nificant wave height (eq. 4-26) 



Sediment-size standard deviation 

 in phi units 



2 



FT^/L^ 



Example Units 



Metric 



FT^/L^ 



„-l 



2, 

 m /s 



H 2, 4 , 

 N-s /m (or 



1, 2, 4, 

 kg-s /m ) 



VI 2, 4 , 

 N-s /m (or 



1. 2, 4, 

 kg-s /m ) 



-1 



English 



rad 

 deg 



deg 

 deg 

 deg 



2 

 ft /s 



ft 



ft 



Ib-s^/ft^ 



IK 2, 4 

 Ib-s /m 



Ib-s^/it'' 



Ib-s^/ft^ 



Ib-s^/ft^ 



Ib-s^/ft* 



Ib-s^/ft* 



phi 



(Continued) 



t 2 



Note: the SI unit of weight (meaning force, or mass accelerated at the standard free-fall rate of 9.80665 m/s ) 



2 

 is the newton, which is equal to 1 kg-m/s . When computing armor unit weights for practical purposes, newtons 



can be converted to kilograms (mass) by multiplying by 9.80665. 



B20 



