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GRADUALLY VARIED FLOW

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INTRODUCTION

A STEADY NON-UNIFORM FLOW IN A PRISMATIC

CHANNEL WITH GRADUAL CHANGES IN ITS WATER

SURFACE ELEVATION

THE CHANGES IN THE DEPTH AND VELOCITY

OCCUR GRADUALLY OVER A CONSIDERABLE

LENGTH OF CHANNEL.

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Slope S0, is classified as :

Mild (M) : yn > yc

Steep (S) : yn< yc

Critical (C) : yn = yc

Horizontal (H) : S0 = 0

Adverse (A) : S0 < 0

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FLOW ZONE

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GVF- PROFILE TYPES

Type of flow profile for gradually varied flow is written with

FONT and NUMBER

FONT > slope type

NUMBER > flow zone

M1 M2 M3

S1 S2 S3

C1 C2 C3

X H2 H3

X A2 A3

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FLOW PROFILE - MILD

SLOPE

Dam

CDL

NDLM1

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Sluice gate

Hydraulic jump

M3

M2

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FLOW PROFILE -

STEEP SLOPE

Hydraulic jump

Dam

NDL

CDLS2

S1

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Sluice gate

S3NDL

CDL

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FLOW PROFILE -

CRITICAL SLOPE

Hydraulic jump

C1

weir

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C2

C3

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H2

H3

Sluice gate

Flow profile - horizontal slope

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FLOW PROFILE -

ADVERSE SLOPE

CDL

A2

A3

CDL

Sluice gate