TABLE OF CONTENTS To simplify using the formulas in this chapter, Table 12.1 presents symbols, nomenclature, and United States Customary System (USCS) and System International (SI) units found in each expression.
| Symbol | Terminology | Dimensions | USCS units | SI units |
|---|---|---|---|---|
| Symbol | Terminology | Dimensions | USCS units | SI units |
| A | Area | L 2 | ft 2 | mm 2 |
| C | Chezy roughness coefficient | L 1/2/ T | ft 5/s | m 0.5/s |
| C 1 | Hazen Williams roughness coefficient | L 0.37/ T | ft 0.37/s | m 0.37/s |
| d | Depth | L | ft | m |
| d c | Critical depth | L | ft | m |
| D | Diameter | L | ft | m |
| E | Modulus of elasticity | F/L 2 | lb/in 2 | MPa |
| F | Force | F | lb | N |
| g | Acceleration due to gravity | L/T 2 | ft/s 2 | m/s 2 |
| H | Total head, head on weir | L | ft | m |
| h | Head or height | L | ft | m |
| h f | Head loss due to friction | L | ft | m |
| L | Length | L | ft | m |
| M | Mass | FT 2/ L | lb s 2/ft | Ns 2/m |
| n | Manning s roughness coefficient | T/L 1/3 | s/ft 1/3 | s/m 1/3 |
| P | Perimeter, weir height | L | ft | m |
| P | Force due to pressure | F | lb | N |
| p | Pressure | F/L 2 | psf | MPa |
| Q | Flow rate | L 3/ T | ft 3/s | m 3/s |
| q | Unit flow rate | L 3/ T L | ft 3/(s ft) | m 3/s m |
| r | Radius | L | ft | m |
| R | Hydraulic... |
