This document summarizes the development of numerical and experimental models for near-field overflow dredging plumes. Laboratory experiments were conducted to study sediment plume behavior and validate computational fluid dynamics (CFD) models. A lab-scale CFD model was developed using large eddy simulation and validated against experimental data. This model was then upscaled to a real-scale model of a trailing suction hopper dredger. Field measurements were also taken and used to validate the real-scale model. The validated models can be used to develop a simplified parameter model for real-time plume forecasting and to study the influence of factors like ship design on plumes.

1. Numerical and Experimental Modelling of
Near-Field Overflow Dredging Plumes
Boudewijn Decrop
Belgian Hydraulics Day
Flanders Hydraulic Research
5/10/2015

2. 7-Oct-15 / Belgian Hydraulics Day/ slide 2
Introduction
Numerical and Experimental Modelling of
Near-Field Overflow Dredging Plumes

3. 7-Oct-15 / Belgian Hydraulics Day/ slide 3
TSHD
Research
Hypothesis
Introduction

4. 7-Oct-15 / Belgian Hydraulics Day/ slide 4
Introduction
General objective:
To develop a 3D near-field plume model of which the
output is used as sediment source for far-field plume
models, which renders far-field plume predictions more
accurate.
This leads to improved forecasting of the plume behaviour
and therefore to a reduced environmental impact
WHY?

5. 7-Oct-15 / Belgian Hydraulics Day/ slide 5
Introduction
 Plume prediction modelling: far-field + near-field models
Large-scale far field models at IMDC (unstructured)
Persian
Gulf Gulf of
Oman
Gulf of
Aden
Red
Sea
Indian
Ocean
iCSM
Tethys model

6. 7-Oct-15 / Belgian Hydraulics Day/ slide 6
Introduction
Plume predictions Environmental management
Sea current (from model)

7. 7-Oct-15 / Belgian Hydraulics Day/ slide 7
Introduction
Plume predictions Environmental management
Sea current (from model)

8. 7-Oct-15 / Belgian Hydraulics Day/ slide 8
Introduction
Plume predictions Environmental management
Sea current (from model)

9. 7-Oct-15 / Belgian Hydraulics Day/ slide 9
Introduction
Plume predictions Environmental management
Sea current (from model)

10. 7-Oct-15 / Belgian Hydraulics Day/ slide 10
Introduction
Plume predictions Environmental management
Sea current (from model)
MAIN RESEARCH QUESTION:
How much sediment to put in the far-field
model and how is it distributed??

11. 7-Oct-15 / Belgian Hydraulics Day/ slide 11
Introduction
Plume predictions Environmental management
Sea current (from model)
TODAY:
* Assumptions with weak justification
* ‘Best guess’ sediment distribution

12. 7-Oct-15 / Belgian Hydraulics Day/ slide 12
Introduction
Plume predictions Environmental management
Sea current (from model)
SOLUTION:
Develop a new near-field model to simulate
detailed flow near ship!

13. 7-Oct-15 / Belgian Hydraulics Day/ slide 13
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

14. 7-Oct-15 / Belgian Hydraulics Day/ slide 14
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENTLab
EXPERIMENTS

15. 7-Oct-15 / Belgian Hydraulics Day/ slide 15
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Lab-scale
MODEL

16. 7-Oct-15 / Belgian Hydraulics Day/ slide 16
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Model matches Experiment ?

17. 7-Oct-15 / Belgian Hydraulics Day/ slide 17
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Next step: validate upscaling to real-life scale

18. 7-Oct-15 / Belgian Hydraulics Day/ slide 18
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Real-scale
MODEL

19. 7-Oct-15 / Belgian Hydraulics Day/ slide 19
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Real-scale
MEASUREMENT

20. 7-Oct-15 / Belgian Hydraulics Day/ slide 20
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Model matches Field Measurements ?

21. 7-Oct-15 / Belgian Hydraulics Day/ slide 21
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Applications:
*Simplified Model
*Influence factors
* Ship Design

22. 7-Oct-15 / Belgian Hydraulics Day/ slide 22
Experiments
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

23. 7-Oct-15 / Belgian Hydraulics Day/ slide 23
Results Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

24. 7-Oct-15 / Belgian Hydraulics Day/ slide 24
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

25. 7-Oct-15 / Belgian Hydraulics Day/ slide 25
Lab-scale Model
• Navier-Stokes eq’s for the mixture
• Large-Eddy Simulation (LES)
• Dynamic Smagorinsky SGS model
• Inflow:
• water+sediment in pipe
• flume crossflow
• Solution
• ∆t = 0.02 s
• CFL = max. 1
• Variables:
• pressure
• velocity components
• sediment fraction
• sub-grid scale variables
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Water + sediment mixture (pipe)
Background
water flow
(crossflow)

26. 7-Oct-15 / Belgian Hydraulics Day/ slide 26
Results
• Mesh, initial:
Schematised hull
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

27. 7-Oct-15 / Belgian Hydraulics Day/ slide 27
Results
• Mesh adaptation
• Based on |S| and C (from RANS run)
• Optimised number of cells (~106)
Based on C
Based on strain rate |S|
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

28. 7-Oct-15 / Belgian Hydraulics Day/ slide 28
Results
• Impression of the sediment plume
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

29. 7-Oct-15 / Belgian Hydraulics Day/ slide 29
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Model matches Experiment ?

30. 7-Oct-15 / Belgian Hydraulics Day/ slide 30
Results
• Qualitatively:
Visually : Lab vs CFD
Stable stratification
Unstable stratification
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

31. 7-Oct-15 / Belgian Hydraulics Day/ slide 31
Results
Quantitatively:
1. Trajectory : Laboratory vs CFD
• Centerline
• Upper/lower edge
• Plume entrainment due to vessel hull
Decrop, B. et al. (2015). Large-Eddy Simulations of turbidity plumes in crossflow. European Journal of Mechanics - B/Fluids (53), p68-84,
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

32. 7-Oct-15 / Belgian Hydraulics Day/ slide 32
Results
Quantitatively:
2. SSC & Turbulence
• RMS ui’
• RMS c’
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

33. 7-Oct-15 / Belgian Hydraulics Day/ slide 33
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Model matches Experiment ? YES!

34. 7-Oct-15 / Belgian Hydraulics Day/ slide 34
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

35. 7-Oct-15 / Belgian Hydraulics Day/ slide 35
Real-scale model
• Full-size TSHD
• Propellers included (actuator disk)
• Dynamic air bubble transport model:
• Lagrangian,
• Forces: drag, virtual mass, grad(p), g
• Coalescence
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

36. 7-Oct-15 / Belgian Hydraulics Day/ slide 36
Real-scale model
• Mesh details
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

37. 7-Oct-15 / Belgian Hydraulics Day/ slide 37
Real-scale model
! Validation needed  Monitoring campaigns
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Deep water, light mixture
Shallow water
Air bubble concentration
Deep water, heavy mixture

38. 7-Oct-15 / Belgian Hydraulics Day/ slide 38
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

39. 7-Oct-15 / Belgian Hydraulics Day/ slide 39
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Model matches Field Measurements ?

40. 7-Oct-15 / Belgian Hydraulics Day/ slide 40
Results Validation CFD
Validation Case 1:
• H=16m ; D=2m; W0=1.9 m/s; U∞=1.5 m/s, C0=55 g/l
• CPU time: 25 hours at 32 CPU’s

41. 7-Oct-15 / Belgian Hydraulics Day/ slide 41
Results Validation CFD
Validation Case1: Vertical profiles
• Measurement carried out at < 200 m for near-field validation
• Compared with time-averaged model results
Measured
CFD Model

42. 7-Oct-15 / Belgian Hydraulics Day/ slide 42
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Model matches Field Measurements ?
YES!

43. 7-Oct-15 / Belgian Hydraulics Day/ slide 43
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Applications:
*Simplified Model
*Influence factors
* Ship Design

44. 7-Oct-15 / Belgian Hydraulics Day/ slide 44
Overview Model development
Applications:
*Simplified Model
*Influence factors
* Ship Design

45. 7-Oct-15 / Belgian Hydraulics Day/ slide 45
Application to turbidity forecasting
• Fast parameter model (< 1 sec.)
• Programmed inside far-field modelling software  real-time
evolution of overflow flux
• Source terms: function of
• Current velocity and direction
• Sailing speed
• Sediment Concentration, % fines
• Overflow diameter and position
Far field model
Near-field
Parameter model
Current
Source terms
Parameters from CFD data fits
Applications:
*Simplified Model
*Influence factors
* Ship Design

46. 7-Oct-15 / Belgian Hydraulics Day/ slide 46
General Conclusions
• 3D, multiphase CFD model
• Validated in the laboratory + the field
• Applied for:
• Parameterisation
• Overflow design
• Influence factors

47. THE END

48. 7-Oct-15 / Belgian Hydraulics Day/ slide 48
Setup: Test case ‘Vertical plume’
• Geometry:
• Vertical plume as a first test case for the CFD model
• Mesh:
• Unstructured tet mesh
• ‘Inflation layers’ near walls (pipe)
• Mesh ‘Adaptation’:
1. RANS simulation on relatively coarse mesh
2. Refinement where gradients / SSC significant
3. RANS on refined mesh
4. LES
w
u
z
r

49. 7-Oct-15 / Belgian Hydraulics Day/ slide 49
Setup: Test case ‘Vertical plume’
• Results
• Self-similarity for z/D > 8
• Comparison with experiments
• Good accuracy time-averaged W(r) and C(r)
Decrop, B. et al. (2015). New methods for ADV measurements of turbulent sediment fluxes – Application to a fine sediment plume. Journal of
Hydraulic Research 53 (3), p 317-331,

50. 7-Oct-15 / Belgian Hydraulics Day/ slide 50
Setup: Test case ‘Vertical plume’
• Results
• Reynolds stresses accurate: peak value, peak location
• Turbulent fluctuations C: radial profile correct
Decrop, B. et al. (2015). New methods for ADV measurements of turbulent sediment fluxes – Application to a fine sediment plume. Journal of
Hydraulic Research 53 (3), p 317-331,

51. 7-Oct-15 / Belgian Hydraulics Day/ slide 51
Experiments Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Goal of the experiments:
• Insights in sediment plume behaviour
• Produce data set to compare with model results
• Preliminary estimate of influence factors:
• Air bubbles
• Ship hull

52. 7-Oct-15 / Belgian Hydraulics Day/ slide 52
• 34 different plumes at scale 1/50
• Flume: length = 15m, width = 0.8 m, depth = 0.6 m
• W0 = 4 – 30 cm/s; C0 = 5 – 50 g/l; D = 3.4 – 6.5 cm
• Sediment: kaolin, d50=4 μm
• Dynamically scaled:
• Densimetric Froude number FΔ
• velocity ratio λ
Experiments
Upstream
reservoir
Downstream
reservoir
ASM 2
ASM 1
ADV’s
Valve
Honeycomb
Ship ‘hull’
x
z
y
U0
ρ∞
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

53. 7-Oct-15 / Belgian Hydraulics Day/ slide 53
Results
1. Plume trajectory
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
2. Profiles of:
• Sed. concentration
• Velocity components
• Turbulent properties
3. Influence factors
Air bubbles
Ship hull

54. 7-Oct-15 / Belgian Hydraulics Day/ slide 54
Lab-scale Model
• Navier-Stokes eq’s for the mixture
• Models:
• Multiphase: mixture model (with drift flux term, slip velocity, drag)
• Turbulence: Large-Eddy Simulation (LES)
• SGS model: Dynamic Smagorinsky
 each (x,y,z,t): t, Dt and Sct
• Phases mixture model:
• Liquid phase: fresh water
• Sediment: spherical, d=4 µm
• Stokes number << 1
• Volume concentration 0.2 to 4%
• Inflow boundary: spectral synthesizer (vortex mimicking)
• Water surface: rigid lid
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

55. 7-Oct-15 / Belgian Hydraulics Day/ slide 55
Setup : Plume in crossflow
• Mesh, initial:
Schematised hull

56. 7-Oct-15 / Belgian Hydraulics Day/ slide 56
Setup : Plume in crossflow
• Mesh, refined
• Optimised number of cells (~106)
Based on C (from RANS run)
Based on strain rate

57. 7-Oct-15 / Belgian Hydraulics Day/ slide 57
Results
• Qualitatively : well-known turbulent structures are present:
2. Counter-rotating vortex pair + double C-peak
PIV/PLIF
measurements,
Diez et al. (2005)
CFD

58. 7-Oct-15 / Belgian Hydraulics Day/ slide 58
Validation case : Bubble plume in crossflow
• Case of Zhang et al. (2013)
• Upward bubbly jet (20 vol.% air)
• Tracer in jet fluid
• Centerline tracer plume
• Centerline bubble plume
• LES model with three phases:
• Water
• Sediment (tracer)
• Air bubbles:
• Initial diameter: 1.7 mm
• Collision model
Coalescence  bubble size distribution
• Influence bubbles on sediment plume: ok
• Separation bubble plume: ok
Sediment plume
Separating bubble plume

59. 7-Oct-15 / Belgian Hydraulics Day/ slide 59
Results
Quantitatively:
3. Turbulent Kinetic Energy k
Decrop, B. et al. (2015). Large-Eddy Simulations of turbidity plumes in crossflow. European Journal of Mechanics - B/Fluids (53), p68-84,
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

60. 7-Oct-15 / Belgian Hydraulics Day/ slide 60
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Next step: validate upscaling to real-life size

61. 7-Oct-15 / Belgian Hydraulics Day/ slide 61
Upscaling to realistic scale:
CFD model with lab geometry

62. 7-Oct-15 / Belgian Hydraulics Day/ slide 62
Upscaling LES model to prototype scale
1. Take CFD model lab scale
2. Scale grid to large scale
(similarity laws buoyant jets)
3. CFD simulation
4. Validation, based on:
• Trajectories in similarity
coordinates must coincide with
lab scale
• TKE resolved > 80%, for LES
completeness (Pope, 2004)
CFD (large scale, Re=1.9 106)
Physical model (small scale, Re=1.2 104)

63. 7-Oct-15 / Belgian Hydraulics Day/ slide 63
Results Validation CFD
• Density current + Surface plume (air bubbles, propellers)
• 5% of sediments released to ‘far-field’ plume
• Hypothesis confirmed?
near-bed density current
surface plume

64. 7-Oct-15 / Belgian Hydraulics Day/ slide 64
Measurements
Determination of sediment
concentration:
• Sampling inside the overflow (to
impose in model runs)
• Measurements and samples in the
dredging plume
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

65. 7-Oct-15 / Belgian Hydraulics Day/ slide 65
Measurements
SiltProfiler:
• High-res. vertical profiler (free-fall,100 Hz)
• Wireless connection when above water
(BlueTooth)
• CTD
• 3-step turbidity sensor (0 – 50,000 mg/l)
• Design avoids seabed disturbance
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT

66. 7-Oct-15 / Belgian Hydraulics Day/ slide 66
Measurements
SiltProfiler results
Consistent profile type:
1. Diluted surface plume: 10-200 mg/l
2. Near-bed layer, 2-6m thick: 200-1500 mg/l

67. 7-Oct-15 / Belgian Hydraulics Day/ slide 67
Measurements
Transect sailing (near-field, 100-500m from stern)
Across the plume Along the plume

68. 7-Oct-15 / Belgian Hydraulics Day/ slide 68
Results Validation CFD (Site 2)
• Validation Case 2:
• Data from earlier campaign
• H=39m ; D=1.1m ; W0=3.2 m/s; U∞=1.5 m/s, C0=10 g/l
 In some cases: 100% of sediment released to far-field plume
log(C/C0)
CFD model
: ADCP: Bottom of plume

69. 7-Oct-15 / Belgian Hydraulics Day/ slide 69
Validation prototype scale CFD (Case 2)
Case 2: Surface plume (OBS measurements)
• In situ measurements: lumped, crossing the plume
• Model output: at centreline
 Cmax,insitu should be = Ccentreline,model

70. 7-Oct-15 / Belgian Hydraulics Day/ slide 70
Results Validation CFD (Site nr 2)
Validation Case 2:
• H=39m ; D=1.1m ; Overflow near stern
 In contradiction to hypothesis: 100% of sediment released to far-field plume
log(C/C0)
CFD model
: Measured bottom of plume

71. 7-Oct-15 / Belgian Hydraulics Day/ slide 71
Environmental valve efficiency
• 2x 26 cases, with/without valve
• Valve efficiency = function of surface plume sediment flux with/without
valve

72. 7-Oct-15 / Belgian Hydraulics Day/ slide 72
Environmental valve efficiency
• Valve efficiency turns out to be related to a combination of length
scales and a Froude number

73. 7-Oct-15 / Belgian Hydraulics Day/ slide 73
Environmental valve efficiency
• Decomposition in constructional and operational efficiency
• Operation has more impact on efficiency than construction
influence diameter and overflow position influence sailing speed and sediment concentration

74. 7-Oct-15 / Belgian Hydraulics Day/ slide 74
Influence on surface turbidity
• Number of overflows

75. 7-Oct-15 / Belgian Hydraulics Day/ slide 75
Influence on surface turbidity
• Sediment load
 sediment fraction in surface plume much larger for low C0
C0=10 g/l
C0=150 g/l
log(C/C0)
log(C/C0)
Applications:
*Simplified Model
* Ship Design

76. 7-Oct-15 / Belgian Hydraulics Day/ slide 76
Parameter model
• Motivation: CFD model has high CPU cost, not practical in some cases
Find a simple model that is:
1. Much faster
2. Almost as accurate
A model with output:
 In suitable form for far-field models input
 Vertical profile of sediment flux behind ship
• Parameter model = combination of
• Analytical plume solutions
• Parameter fits on data of +/- 100 CFD model runs
Applications:
*Simplified Model
*Influence factors
* Ship Design

77. 7-Oct-15 / Belgian Hydraulics Day/ slide 77
Parameter model
• O(100) CFD runs, with variation of:
• Current velocity
• Sailing speed
• Sediment concentration
• Overflow diameter, position
• Air bubble concentration
 For ‘Model Training’
• Model Validation: against extra
dataset CFD results
• 90% has R²>0.5
• Valid for standard cases, for
specific cases still CFD needed
CFD
Par. Mod.
Applications:
*Simplified Model
*Influence factors
* Ship Design

78. 7-Oct-15 / Belgian Hydraulics Day/ slide 78
Overview Model development
Applications:
*Simplified Model
*Influence factors
* Ship Design

79. 7-Oct-15 / Belgian Hydraulics Day/ slide 79
Influence of air bubbles
• Environmental valve: air bubbles -90% (Saremi, 2014)
• Perform simulations with/without air flow rate reduction
Surface plume
No surface plume
log(C/C0)
Applications:
*Simplified Model
*Influence factors
* Ship Design

80. 7-Oct-15 / Belgian Hydraulics Day/ slide 80
Influence of velocity
Relative velocity sea water - ship
 sediment in surface plume x 10
2 knots
6 knots
log(C/C0)
Applications:
*Simplified Model
*Influence factors
* Ship Design

81. 7-Oct-15 / Belgian Hydraulics Day/ slide 81
Overview Model development
Applications:
*Simplified Model
*Influence factors
* Ship Design

82. 7-Oct-15 / Belgian Hydraulics Day/ slide 82
Overflow position
• Overflow at stern: plume mixed by propellers
• Overflow at aft: plume has more time to descend
Ship
Applications:
*Simplified Model
*Influence factors
* Ship Design
log(C/C0)

83. 7-Oct-15 / Belgian Hydraulics Day/ slide 83
Overflow shaft extension
• Studied earlier by de Wit et al. (2015)
• C at surface reduced with factor up to 10
• Still surface plume because of rising air
bubbles
dair
Ship
extension
Applications:
*Simplified Model
*Influence factors
* Ship Design
log(C/C0)

84. 7-Oct-15 / Belgian Hydraulics Day/ slide 84
Rectangular overflow shaft
 Potentially 50% reduction of sediment concentration
Applications:
*Simplified Model
*Influence factors
* Ship Design
Aspect ratio 1:3

85. 7-Oct-15 / Belgian Hydraulics Day/ slide 85
Overview Model development
Lab
EXPERIMENTS
Lab-scale
MODEL
Real-scale
MODEL
Real-scale
MEASUREMENT
Applications:
*Simplified Model
*Influence factors
* Ship Design

86. 7-Oct-15 / Belgian Hydraulics Day/ slide 86
Future research and applications
Overflow design (CFD model)
• Detailed study efficiency of:
• Shaft extension
• Rectangular overflow
• Influence of:
• Lateral position overflow
• Number of overflows
• Inclined overflow exit?
• Overflow via draghead jetting
Parameter model
• Real-time plume forecasting
• Tender-phase dredging strategy