ANSYS Applications in Ocean Science and Engineering

ANSYS Applications in Ocean 

Science and Engineering 

1 

© 2011 ANSYS, Inc. August 12, 2011 

Marsall Loewenstein 

Ian Lockley 

8/10/2011

Perspective 

The Universe in One Year concept was inspired by the 

late Cornell astronomer, Carl Sagan. Sagan was the first 

person to explain the history of the universe in one 

year—as a “Cosmic Calendar”—in his television series, 

Cosmos 

2 

© 2011 ANSYS, Inc. August 12, 2011

Perspective 

3 


0.5 Seconds of Oceanographic History 

11:59:59.5 seconds…. 

1769 

Benjamin Franklin’s first scientific study of the Gulf Stream. He measured 

water temperatures during several Atlantic crossings and effectively 

explained the phenomena. 

4 


5 


0.5 Seconds of Oceanographic History 

11:59:59.5 seconds…. 

1769 

Benjamin Franklins first scientific study of the Gulf Stream. He measured 

the water temperatures during several Atlantic crossings and effectively 

explained tbe phenomena 

1855 

Physical Geography of the Sea, by Matthew Fontaine Maury published in 

1855 was the first textbook of Oceanography. 

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Relevance to Science / Engineering / Product Design 

• The pace of academic endeavors, discovery and information continues to 

grow at an exponential rate 

• Scientists and Engineers are constantly challenged or asked to do more 

with less 

• Time and expense of developing industrial and research equipment test 

must be reduced 

• Quality and safety must continue to rise 

• We must all be stewards of our precious environment 

• “Cut and try” approaches in science and engineering must be 

supplemented or replaced with simulation 

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• Many mature software tools exist from ANSYS, across an 

enormous range of physical disciplines, which enable 

research and the development and testing of both concepts 

and products through physics based numerical simulation 


Overview 

• Brief Introduction to ANSYS 

• Selected Simulation Applications 

– Environmental 

– Pollution dispersion, cleanup, scouring, 

ocean currents, noise … 

– Energy 

– Wave energy, tidal energy, energy 

environmental impact 

– Marine 

– Hull design, propulsion, system design, 

sensor design …. 

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Overview 






– Energy 






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Who is ANSYS 

Focused 

This is all we do: Physics based software simulation tools for 

science and engineering 

Capable 

2,000 employees 

60 locations, 40 countries 

Trusted 

96 of top 100 FORTUNE 500 industrials 

Proven 

Recognized as one of the world’s most innovative 

and fastest-growing companies* 

A 40 year track record of innovation 

Independent 

Long-term financial stability 

CAD agnostic 

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*BusinessWeek, FORTUNE 

(image of engineer working through simulation problem)

One Picture of ANSYS 

ANSYS is the leading provider of 

physics based engineering 

software tools 

Paramterization 

Fluids 

Meshing 

• Structural 

• Thermal 

• Electromagnetics 

and 

• Fluids 

CAD 

Import 

Structural 

+ 

- 

u(t) 

In-house 

D(s) Plant 

Solution 

y(t) 

Emag 

Thermal 

Workflow 

Postprocessing 

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Industry Leading Customers 

12 


Selected Academic Customers 

13 


ANSYS Academic Program 

Presence 

• Academic products used at 2,400 institutions 

worldwide, with nearly 87,000 licensed seats 

Value to Industry 

• Students trained in ANSYS join industry with 

experience in simulation 

• Research use of ANSYS helps tackle next-generation 

industry challenges 

Software Technology 

• Academic partnerships ensure our product 

technology leadership 

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“By embedding ANSYS technology in our engineering curriculum, Cornell is producing 

students who can go into industry with a strong foundation in the application of 

advanced simulation.” 

Dr. Rajesh Bhaskaran 

Cornell University 

ANSYS Academic Program 

Professor Rajesh Bhaskaran 

Cornell University

Typical Marine CFD Applications 

• Hydrodynamics 

• Ship hulls 

• Submarines 

• Yacht hulls, keels 

• Appendages 

• Other underwater systems 

• Towed sonar arrays 

• Propulsion 

• Propeller / Hull 

interactions 

• Water jets 

• Cavitation 

• Bubble wakes and 

signature 

• Acoustics 

• Aerodynamics 

• Superstructures 

• Dispersion 

• Yacht Sails 

• Exhaust plumes 

• Ventilation 

• Heli Deck operations 

• Fire Suppression 

• Halon replacement 

• Blast interactions 

• Fluid Structure Interaction 

• Floating objects 

• Flexible objects 

• Vortex Induced Vibration 

• Swim suits 

• Heat transfer 

• Fuel Cells 

• Wave slam 

• Flooding in Ro-Ro ferries 

• Cavitation 

• Torpedoes 

• Sloshing in tanks 

• Submarine Reactors 

• Structural vibrations 

• Periscope / free surfaces 

• Pumps 

• Offshore Power 

generation 

• Chemical reactions 

• Free surface flows 

• Microfluidics 

• Hypersonics 

• CVD 

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Overview 






– Energy 






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Overview 






– Energy 






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Environmental: Scouring 

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Scouring: Challenges 

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Scouring: Examples 

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CFD modeling of scour around offshore wind turbines in areas with 

strong currents, Solberg et al, Conference on Offshore Wind 

Turbines Situated in Strong Sea Currents, 2006 

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Advanced numerical modeling of the scouring process 

around the piers of a bridge, Motta et al, Proc of the 

congress, IAHR, 2007 

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Illustration Problem 

24 


Modeling Approach 

25 


Initial Results 

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Numerical simulation of scour around pipelines using an 

Euler-Euler coupled two-phase model, Zhao and 

Fernando, Environmental Fluid Mechanics, (2007) 

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Environmental: Oil Spill and Cleanup 

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Environmental: Oil Spill and Cleanup 

29 


CFD Modeling of Oil Spill 

Past CFD studies employed VOF approach to study oil spill 

• Free surface was captured by VOF 

• Linear wave profiles was used to describe wave boundary condition 

• Studies were limited to 2D 

• Studies were conducted for different wavelength and amplitude 

30 

30 


Current CFD Model 

Full 3-dimensional Model 

Volume of Fluid (VOF) – Approach 

• A single set of momentum equations is solved and the volume 

fraction of each immiscible phase is tracked 

• Three phases – Air, Water and Oil is considered 

Open channel wave boundary condition -used 

to prescribe wave motion 

A fifth order stokes wave theory is used to 

describe a non-linear wave 

Turbulence – Realizable k-ε model 

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31 


3D CFD Model 

2 Km 

Open Channel 

Boundary Inlet 

Top Surface - Outlet 

Open Channel 

Pressure Outlet 

Oil Spill Location 

Oil Inlet 

32 

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Around 565,000 Grid Elements Used 

Grid refined near sea surface to capture waves

Wave Profiles 

5m Amplitude and 500m Wavelength Wave 



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Wave Profile - Animation 

5m amplitude and 500m Wavelength wave 

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Wave Velocity Profiles 




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Observations - Velocity Profiles 

High velocity near surface due to waves 

As wave steepness increase – Non linear waves results 

Coastal region or Shallow water region impacts the wave profile 

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Oil Slick at Sea Surface 

5m Amplitude and 500m 

Wavelength Wave 





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Time History of Spread 



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0.1m/s - Wave Current 

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Observations 

Spread pattern is different for different wave 

conditions 

Polluted area increases with higher interaction 

of wave and current 

Polluted area is more towards coastal area or in 

shallow water 

High wave amplitude – oil traveled faster to the 

coastal area – thus not spreading 

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Conclusions 

Overview of the oil spill and its impact on oil and gas 

industry 

Physics of oil spill – Hydrodynamics of Ocean waves 

plays major role 

Focused on shallow water waves – Dispersion of oil 

slick is more 

Need higher order wave theories as wave steepness 

increase 

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Conclusions 

43 

43 

Presented a detailed 3D CFD based model for 

study of oil spill 

• Volume of Fluid (VOF) 

• Open channel wave boundary condition 

Spread pattern is different for different wave 

conditions 

Polluted area increases with higher interaction 

of wave and current 

Value of using CFD based simulations for oil spill 

scenarios 


Environmental/Marine: Noise 

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MENCK hydraulic hammer 

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Comparison of measured and calculated underwater sound pressure at 

a distance of 245 meters from the pile. Knowing the sound propagation 

law for this region, the sound pressure at 750 meters can be calculated 

and converted into decibels (dB). 



1 

2 

3 

4 

5 

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Underwater sound generation and propagation 

shown as a sequence of snapshots in time. 

Within a steel pile, the speed of sound is about 

5,000 meters per second, while the speed of 

sound in water is about 1,500 meters per 

second — resulting in radiation patterns and 

specific inclination angle. 

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Overview 






– Energy 






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Energy: Wave Energy 

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1 2 3 

Wave direction 

4 5 

COLUMBIA POWER’s wave power system: The wings and vertical spar 

react to the shape of the passing ocean swell. Each wing is coupled by a 

drive shaft to turn its own rotary generator. 

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COLUMBIA POWER engineers doubled 

efficiency of the buoy by using ANSYS AQWA to 

optimize its geometry. 

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Maxwell computational 

electromagnetics software 

from ANSYS was used to 

optimize the generator 

design. 

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Overview 






– Energy 






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Propulsion Systems 

Rolls-Royce uses simulation for propeller design to reduce 

marine fuel consumption. 

According to a 2003 study from the University of Delaware, international 

commercial and military shipping fleets consume approximately 289 million 

metric tons of petroleum per year, which is more than twice the consumption of 

the entire population of Germany. The ANSYS FLUENT simulations run on the 

modified propeller geometry predicted that the efficiency would increase by 1 

percent to 1.5 percent, and physical experiments confirmed that this was, in 

fact, the case. 

The new Kamewa 

CP-A propeller 

from Rolls-Royce 

Marine 

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Contours of pressure coefficient for the XF5 (left) and the new Kamewa CP-A (right). Insets: Photographs of the blade indicating the locations of the 

simulation where cavitation is present (noticeable as pitting). ANSYS FLUENT results helped reduce pressure at the blade root in the CP-A design, indicated 

by the lack of cavitation erosion present in the CP-A photo. 


Propulsion Systems 

Cavitation Effects 

For water pumps, marine propellers, and other 

equipment involving hydrofoils, cavitation can cause 

problems such as vibration, increased hydrodynamic 

drag, pressure pulsation, noise, and erosion on solid 

surfaces. Most of these problems are related to the 

transient behaviour of cavitation structures. To better 

understand these phenomena, unsteady 3D simulations 

of cavitating flow around single hydrofoils are often 

performed and the results are compared to experiments 

55 

Unsteady propeller cavitation in the wake of a ship 


Courtesy SVA-Potsdam (Potsdam Model Basin)

Propulsion (including Cavitation) 

Cavitating Flow Over a Hydrofoil 

Cavitating flow over a cambered two-dimensional wing 

section was simulated using ANSYS Fluent CFD solver. The 

flow angle over the NACA 66 (MOD) hydrofoil is chosen to 

represent conditions that are common in water pump and 

marine propeller applications. Excellent agreement with 

experimental data is obtained for mid-chord cavitation, and 

satisfactory agreement is obtained at the trailing edge of the 

cavitation region. 

Pressure coefficient as a function of normalized chord length 

showing ANSYS Fluent results compared with experimental data 

Contours of vapour volume fraction show cavitation in the mid-chord region 

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Marine: Sensor Design 

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Conclusions 

ANSYS offers a broad and technically deep set of 

physics based research and engineering 

software tools which foster understanding, 

innovation as well as save time and money 

ANSYS is a strong partner for both academic and 

industrial organizations seeking such goals 

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Thanks You! 

Questions? 

marshall.loewenstein@ansys.com 

Ian.lockley@ansys.com 

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ANSYS Applications in Ocean Science and Engineering

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