Thomas P. Scholcz, Christian H. J. Veldhuis
Multi-Objective Surrogate Based Hull-Form Optimization Using High-Fidelity RANS Computations Conference
VII International Conference on Computational Methods in Marine Engineering (MARINE 2017), 2017.
@conference{Scholcz2017,
title = {Multi-Objective Surrogate Based Hull-Form Optimization Using High-Fidelity RANS Computations},
author = {Thomas P. Scholcz, Christian H.J. Veldhuis},
url = {http://www.marin.nl/web/Publications/Publication-items/MultiObjective-Surrogate-Based-HullForm-Optimization-Using-HighFidelity-RANS-Computations.htm},
year = {2017},
date = {2017-05-01},
booktitle = {VII International Conference on Computational Methods in Marine Engineering (MARINE 2017)},
abstract = {RANS-based optimization procedures for ship design become increasingly complex and require the development of more efficient optimization techniques. The four phases of the design procedure are: shape parameterization, global sensitivity analysis, multi-objective optimization and design review. The dimensions of the design space can be mitigated by a smart choice for the shape parameterization and by screening and ranking the design variables in the global sensitivity phase. Subsequently, Surrogate Based Global Optimization (SBGO) is used to reduce the cost of the multi-objective optimization phase. For a practical application it is shown that the computational time reduces from two weeks to only a day when using SBGO instead of applying a Multi-Objective Genetic Algorithm (MOGA) directly to the solver. The design review phase is then used to verify and further develop the optimal design. Here, we focus on automatic ship design techniques which comprises the first three steps of the design procedure. Accelerating the ship design process is subject of ongoing research at the Maritime Research Institute Netherlands, making it useful for practical applications with turnaround times of only a few weeks.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Christian; Gornicz Veldhuis, Tomasz; Scholcz
13th International Symposium on Practical Design of Ships (PRADS), Copenhagen, Denmark, no. ID080, Practical Design of Ships and Other Floating Structures 2016.
@conference{Veldhuis2016,
title = {Ship optimization using viscous flow computations in combination with generic shape variations and Design of Experiments},
author = {Veldhuis, Christian; Gornicz, Tomasz; Scholcz, Thomas},
url = {http://www.marin.nl/web/Publications/Papers/Ship-optimization-using-viscous-flow-computations-in-combination-with-generic-shape-variations-and-Design-of-Experiments.htm},
year = {2016},
date = {2016-09-04},
booktitle = {13th International Symposium on Practical Design of Ships (PRADS), Copenhagen, Denmark},
journal = {Proceedings of PRADS2016 4th – 8th September, 2016 Copenhagen, Denmark},
number = {ID080},
organization = {Practical Design of Ships and Other Floating Structures},
abstract = {This paper discusses a procedure to optimize ship hull forms for minimum required power and best wake field quality, based on viscous flow computations. This research elaborates on an earlier optimization at MARIN (Van der Ploeg and Raven, 2010 and Van der Ploeg, Starke and Veldhuis, 2013). That optimization lead to a clear Pareto front and trends for a systematic variation study for the afterbody of a chemical tanker. In 2016, new steps are taken to ease and generalize the method of hull shape generation. In the previous study the design space was set up by means of ‘manually’ designed basis hull shapes. In the new approach we test the use of generic basis hull shapes which are automatically generated from one initial hull shape. If effective, this approach can speed up the design process significantly. Finally, we want to improve the process even further by using a Design of Exper-iments approach in which the systematic variations are re-placed by a more clever distribution of calculations over the design space. },
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
Joy; Veldhuis Klinkenberg, Christian
CFD for twin gondola aft ship design Conference
Proceedings of PRADS2016, 4th – 8th September, 2016, Copenhagen, Denmark, 2016.
@conference{Klinkenberg2016,
title = {CFD for twin gondola aft ship design},
author = {Klinkenberg, Joy; Veldhuis, Christian},
url = {http://www.marin.nl/web/Publications/Papers/CFD-for-twin-gondola-aft-ship-design.htm},
year = {2016},
date = {2016-09-04},
booktitle = {Proceedings of PRADS2016, 4th – 8th September, 2016, Copenhagen, Denmark},
abstract = {This paper shows a test case in the optimization for a twingondola
ship. In optimizing ships, one can optimize for minimal
resistance or for minimal power. For twin-gondola this
choice is of great importance, due to the asymmetric nature of
the flow coming into the propeller. We first show the optimization
of a twin-gondola ship for resistance only, where the
decrease in resistance is found to be 1.5%. When including the
propeller, using RaNS-BEM coupling, a large difference is
found between inward and outward rotating propeller. The
ship with the largest resistance, requires the least power if the
propeller turns in the right direction. We show that RaNSBEM
coupling could be an efficient method of taking the
propeller rotation direction into account in an optimization
process. The results are also compared to a model test of the
same ship, showing the same trend.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
ship. In optimizing ships, one can optimize for minimal
resistance or for minimal power. For twin-gondola this
choice is of great importance, due to the asymmetric nature of
the flow coming into the propeller. We first show the optimization
of a twin-gondola ship for resistance only, where the
decrease in resistance is found to be 1.5%. When including the
propeller, using RaNS-BEM coupling, a large difference is
found between inward and outward rotating propeller. The
ship with the largest resistance, requires the least power if the
propeller turns in the right direction. We show that RaNSBEM
coupling could be an efficient method of taking the
propeller rotation direction into account in an optimization
process. The results are also compared to a model test of the
same ship, showing the same trend.
Tomasz; van der Ploeg Gornics, Auke; Scholcz
Trim wedge optimization with viscous free surface computations Conference
Proceedings of PRADS2016, Copenhagen, Denmark, 2016.
@conference{Gornics2016,
title = {Trim wedge optimization with viscous free surface computations},
author = {Gornics, Tomasz; van der Ploeg, Auke; Scholcz, Thomas},
url = {http://www.marin.nl/web/Publications/Papers/Trim-wedge-optimization-with-viscous-free-surface-computations.htm},
year = {2016},
date = {2016-09-04},
booktitle = {Proceedings of PRADS2016, Copenhagen, Denmark},
abstract = {A procedure for automatic optimization of a ship hull and
trim wedge is described, that is based on an evaluation
of a series of hull form/trim wedge combinations. These
evaluations are done with a RANS method that can accurately
and efficiently compute the viscous flow for several
transom flow regimes, ranging from completely dry
to (partly) wetted. The object function is an approximation
of the required power to maintain a given speed. Results
obtained from several trim wedge optimizations are
shown, computed and measured trends are compared and
computed scale effects in those trends are discussed. For
two examples, a considerable improvement of the object
function can be obtained. At full scale, the improvement
of the object function is stronger than at model scale.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
trim wedge is described, that is based on an evaluation
of a series of hull form/trim wedge combinations. These
evaluations are done with a RANS method that can accurately
and efficiently compute the viscous flow for several
transom flow regimes, ranging from completely dry
to (partly) wetted. The object function is an approximation
of the required power to maintain a given speed. Results
obtained from several trim wedge optimizations are
shown, computed and measured trends are compared and
computed scale effects in those trends are discussed. For
two examples, a considerable improvement of the object
function can be obtained. At full scale, the improvement
of the object function is stronger than at model scale.
2017
Thomas P. Scholcz, Christian H. J. Veldhuis
Multi-Objective Surrogate Based Hull-Form Optimization Using High-Fidelity RANS Computations Conference
VII International Conference on Computational Methods in Marine Engineering (MARINE 2017), 2017.
Abstract | Links | BibTeX | Tags: Hull-form, Multi-level, Multi-objective, optimization, RANS, Surrogate
@conference{Scholcz2017,
title = {Multi-Objective Surrogate Based Hull-Form Optimization Using High-Fidelity RANS Computations},
author = {Thomas P. Scholcz, Christian H.J. Veldhuis},
url = {http://www.marin.nl/web/Publications/Publication-items/MultiObjective-Surrogate-Based-HullForm-Optimization-Using-HighFidelity-RANS-Computations.htm},
year = {2017},
date = {2017-05-01},
booktitle = {VII International Conference on Computational Methods in Marine Engineering (MARINE 2017)},
abstract = {RANS-based optimization procedures for ship design become increasingly complex and require the development of more efficient optimization techniques. The four phases of the design procedure are: shape parameterization, global sensitivity analysis, multi-objective optimization and design review. The dimensions of the design space can be mitigated by a smart choice for the shape parameterization and by screening and ranking the design variables in the global sensitivity phase. Subsequently, Surrogate Based Global Optimization (SBGO) is used to reduce the cost of the multi-objective optimization phase. For a practical application it is shown that the computational time reduces from two weeks to only a day when using SBGO instead of applying a Multi-Objective Genetic Algorithm (MOGA) directly to the solver. The design review phase is then used to verify and further develop the optimal design. Here, we focus on automatic ship design techniques which comprises the first three steps of the design procedure. Accelerating the ship design process is subject of ongoing research at the Maritime Research Institute Netherlands, making it useful for practical applications with turnaround times of only a few weeks.},
keywords = {Hull-form, Multi-level, Multi-objective, optimization, RANS, Surrogate},
pubstate = {published},
tppubtype = {conference}
}
2016
Christian; Gornicz Veldhuis, Tomasz; Scholcz
13th International Symposium on Practical Design of Ships (PRADS), Copenhagen, Denmark, no. ID080, Practical Design of Ships and Other Floating Structures 2016.
Abstract | Links | BibTeX | Tags: CFD, design of experiments, optimization, power, wake field
@conference{Veldhuis2016,
title = {Ship optimization using viscous flow computations in combination with generic shape variations and Design of Experiments},
author = {Veldhuis, Christian; Gornicz, Tomasz; Scholcz, Thomas},
url = {http://www.marin.nl/web/Publications/Papers/Ship-optimization-using-viscous-flow-computations-in-combination-with-generic-shape-variations-and-Design-of-Experiments.htm},
year = {2016},
date = {2016-09-04},
booktitle = {13th International Symposium on Practical Design of Ships (PRADS), Copenhagen, Denmark},
journal = {Proceedings of PRADS2016 4th – 8th September, 2016 Copenhagen, Denmark},
number = {ID080},
organization = {Practical Design of Ships and Other Floating Structures},
abstract = {This paper discusses a procedure to optimize ship hull forms for minimum required power and best wake field quality, based on viscous flow computations. This research elaborates on an earlier optimization at MARIN (Van der Ploeg and Raven, 2010 and Van der Ploeg, Starke and Veldhuis, 2013). That optimization lead to a clear Pareto front and trends for a systematic variation study for the afterbody of a chemical tanker. In 2016, new steps are taken to ease and generalize the method of hull shape generation. In the previous study the design space was set up by means of ‘manually’ designed basis hull shapes. In the new approach we test the use of generic basis hull shapes which are automatically generated from one initial hull shape. If effective, this approach can speed up the design process significantly. Finally, we want to improve the process even further by using a Design of Exper-iments approach in which the systematic variations are re-placed by a more clever distribution of calculations over the design space. },
keywords = {CFD, design of experiments, optimization, power, wake field},
pubstate = {published},
tppubtype = {conference}
}
Joy; Veldhuis Klinkenberg, Christian
CFD for twin gondola aft ship design Conference
Proceedings of PRADS2016, 4th – 8th September, 2016, Copenhagen, Denmark, 2016.
Abstract | Links | BibTeX | Tags: optimization, propeller, RANS-BEM, rotation direction, twin-gondola
@conference{Klinkenberg2016,
title = {CFD for twin gondola aft ship design},
author = {Klinkenberg, Joy; Veldhuis, Christian},
url = {http://www.marin.nl/web/Publications/Papers/CFD-for-twin-gondola-aft-ship-design.htm},
year = {2016},
date = {2016-09-04},
booktitle = {Proceedings of PRADS2016, 4th – 8th September, 2016, Copenhagen, Denmark},
abstract = {This paper shows a test case in the optimization for a twingondola
ship. In optimizing ships, one can optimize for minimal
resistance or for minimal power. For twin-gondola this
choice is of great importance, due to the asymmetric nature of
the flow coming into the propeller. We first show the optimization
of a twin-gondola ship for resistance only, where the
decrease in resistance is found to be 1.5%. When including the
propeller, using RaNS-BEM coupling, a large difference is
found between inward and outward rotating propeller. The
ship with the largest resistance, requires the least power if the
propeller turns in the right direction. We show that RaNSBEM
coupling could be an efficient method of taking the
propeller rotation direction into account in an optimization
process. The results are also compared to a model test of the
same ship, showing the same trend.},
keywords = {optimization, propeller, RANS-BEM, rotation direction, twin-gondola},
pubstate = {published},
tppubtype = {conference}
}
ship. In optimizing ships, one can optimize for minimal
resistance or for minimal power. For twin-gondola this
choice is of great importance, due to the asymmetric nature of
the flow coming into the propeller. We first show the optimization
of a twin-gondola ship for resistance only, where the
decrease in resistance is found to be 1.5%. When including the
propeller, using RaNS-BEM coupling, a large difference is
found between inward and outward rotating propeller. The
ship with the largest resistance, requires the least power if the
propeller turns in the right direction. We show that RaNSBEM
coupling could be an efficient method of taking the
propeller rotation direction into account in an optimization
process. The results are also compared to a model test of the
same ship, showing the same trend.
Tomasz; van der Ploeg Gornics, Auke; Scholcz
Trim wedge optimization with viscous free surface computations Conference
Proceedings of PRADS2016, Copenhagen, Denmark, 2016.
Abstract | Links | BibTeX | Tags: CFD, free surface, optimization, scale effects, ship hydrodynamics, trim wedge
@conference{Gornics2016,
title = {Trim wedge optimization with viscous free surface computations},
author = {Gornics, Tomasz; van der Ploeg, Auke; Scholcz, Thomas},
url = {http://www.marin.nl/web/Publications/Papers/Trim-wedge-optimization-with-viscous-free-surface-computations.htm},
year = {2016},
date = {2016-09-04},
booktitle = {Proceedings of PRADS2016, Copenhagen, Denmark},
abstract = {A procedure for automatic optimization of a ship hull and
trim wedge is described, that is based on an evaluation
of a series of hull form/trim wedge combinations. These
evaluations are done with a RANS method that can accurately
and efficiently compute the viscous flow for several
transom flow regimes, ranging from completely dry
to (partly) wetted. The object function is an approximation
of the required power to maintain a given speed. Results
obtained from several trim wedge optimizations are
shown, computed and measured trends are compared and
computed scale effects in those trends are discussed. For
two examples, a considerable improvement of the object
function can be obtained. At full scale, the improvement
of the object function is stronger than at model scale.},
keywords = {CFD, free surface, optimization, scale effects, ship hydrodynamics, trim wedge},
pubstate = {published},
tppubtype = {conference}
}
trim wedge is described, that is based on an evaluation
of a series of hull form/trim wedge combinations. These
evaluations are done with a RANS method that can accurately
and efficiently compute the viscous flow for several
transom flow regimes, ranging from completely dry
to (partly) wetted. The object function is an approximation
of the required power to maintain a given speed. Results
obtained from several trim wedge optimizations are
shown, computed and measured trends are compared and
computed scale effects in those trends are discussed. For
two examples, a considerable improvement of the object
function can be obtained. At full scale, the improvement
of the object function is stronger than at model scale.