The new Delta Flume

for large-scale physical model testing

Marcel van Gent

Contents

The new Delta Flume for large-scale physical model testing

1. Introduction

2. The existing Delta Flume

3. The new Delta Flume

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1. Introduction

New Delta Flume part of a system of wave facilities:

L (m) W (m) H (m)

• 2D, small scale: Scheldt Flume 110 1 1.2

• 2D & 3D, small scale: Atlantic Basin 75 8.7 1.3

• 3D, small scale: Delta Basin 50 50 1

• 2D, large scale: Delta Flume 300 5 9.5

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Delta Basin Delta Flume

Scheldt Flume

Atlantic Basin

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2. The existing Delta Flume

Delta Flume

• 2D, large scale testing: Old: 240m*5m*7m

New: 300m*5m*9.5m

• Wave generators: Old: Hs=1.6m (Hmax= 2.5m);

New: Hs=2.2m (Hmax = 4 - 4.5m).

• Accurate active reflection compensation & 2nd order wave generation.

• (Tidal) water level variations New: Pump capacity: 1 m3/s.

• Video observation system, profiler, laser-scanner, radar, etc.

Delta Flume

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2. The existing Delta Flume

Delta Flume

Low-crested structure with cobble beach

Placed block revetments

Wave run-up and wave overtopping

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2. The existing Delta Flume

Delta Flume

Residual strength of dikes

Breakwater stability Dune erosion

Geotubes

Wave damping by brushwood mattresses

3. The new Delta Flume

Why a new Delta Flume?

• Less or no scale effects (the bigger, the better): Dikes, dunes, etc.

• Large potential savings by performing research.

• Existing Delta Flume over 30 years old.

• Need for new large-scale observation / measurement techniques.

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Delta Flume

3. The new Delta Flume

Scale effects

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• Wave impacts

• surface tension (bubble size),

• air compressibility,

• elasticity of the structure,

• Geotechnics (e.g. liquefaction)

• Fall velocity of sediments

• Flow resistance permeable flow

• Turbulent damping

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3. The new Delta Flume

The new Delta Flume

• Large scale testing: 300m*5m*9.5m Hs=2.2m (Hmax =4-4.5m).

• (Tidal) water level variations: Pump capacity: 1 m3/s.

• Video observation system, profiler, laser-scanner, radar, etc.

Delta Flume

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3. The new Delta Flume

Dimensions of the new Delta Flume

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3. The new Delta Flume

Cross-sections of the new Delta Flume

• Measurement carriage (green) and crane (yellow) on separate rails

• Storage reservoir for water

• Access to flume

• Construction of models & installation of measurement equipment

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3. The new Delta Flume

Wave generator of the new Delta Flume

• Water defences in The Netherlands: From 59% to 85% on scale 1:1

Old Delta Flume

New Delta Flume

Old Delta Flume

New Delta Flume

3. The new Delta Flume

Wave generator of the new Delta Flume

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Wave generator of the new Delta Flume

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3. The new Delta Flume

Wave board installation

Wave board with ARC-gauges

Hydraulic power units

Impressions of the new Delta Flume

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3. The new Delta Flume

Test hall and crane (yellow) Height of flume: 9.5 m

Crane on rails

Wave damping slope

3. The new Delta Flume

Measurement techniques in the new Delta Flume

• Video techniques (stereo photography, observation cameras)

• Terrestrial laser scanner

• Mechanical profiler

• Wave gauges, velocity meters, pressure transducers

17 Mechanical profiler Stereo photography Velocities & pressures

Wave gauge

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3. The new Delta Flume

Other aspects of the new Delta Flume

• Soft soil underneath flume: 800 foundation piles (9 km in total).

• 22000 m3 concrete.

• 1850 ton reinforcement steel.

• Storage capacity 9.2 million liter water.

Delta Flume

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3. The new Delta Flume

The new Delta Flume

• Large scale modelling.

• Highest human-made waves (new state-of-the-art wave generation).

• State-of-the-art measurement techniques.

• Experienced staff.

Delta Flume

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Thank you for your attention !

Wave generator: Hmax = 4 m