FLOOD09429

• County: Statewide
• Basin: Statewide
• Title: Hydrologic Engineering Methods for Water Resources Development Volume 6
• Date: 7/1/1975
• Prepared For: US
• Prepared By: US Army Corps of Engineers
• Floodplain - Doc Type: Educational/Technical/Reference Information

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CHAPTER 5. APPLICATION OF THE ONE-DIMENSIOtIAL
ENERGY EQUATION TO NATURAL RIVERS

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Section 5.01. Introduction

The one-dimensional energy equation and supporting functional

relationships and constraints were introduced in Chapter 2. They are

summarized below:

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WS2 +

2
02Q
z
2gA2

- WS +
- 1

2
olQ
2gAZ
1

+ HL

energy equation

(5-1)

Al = f(WSl and cross section geometry)
A2 = f(WS2 and cross section geometry)

(5-2)
(5-3)

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HL = friction and other losses

(5-4)

Q = independent variable (usually)

(5-5)
(5-6)

WSl = f(Q)

WS2

= dependent variable (usually); constrained by
cri ti ca 1 depth

01 = f(WSlo geometry and hydraulic roughness)

(5-7)
(5-8a)

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O2 = f(WS2, geometry and hydraulic roughness)

(5-8b)

The variables A, K and a are non-linear, and often discontinuous

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functions of WS. As a result, equations (5-1) through (5-8b) are
usually solved by the standard step method - a computation method
which uses successive approximations. Cross sections are located to

5.01