Numerical Methods

HSVA has a long lasting experience in developing and applying flow codes primarily for maritime applications. Along with experimental approaches computational fluid dynamics (CFD) is another powerful toolset for approaching several kinds of flow phenomena.

HSVA uses CFD, simulations and other means of numerical approaches to perform design and optimisation tasks and to obtain performance predictions. Numerical tools deliver detailed insight in flow phenomena, including multi-phase flows and multi-body interaction.

The unique advantage of an extensive model test database allows HSVA to routinely validate their numerical predictions for a wide range of vessel types and sailing conditions in order to achieve highest accuracy and robustness of its tools. 

The versatility of HSVA’s flow codes, ranging from low to high complexity-level, allows to address a wide range of typical maritime applications and to offer the customer the most cost-efficient solution for their problem. Beyond that, the flexibility of the codes and HSVA’s expertise in CFD-Software development enables tailor-made solutions for special problems such as adjoint solutions of the flow problem.  

HSVA develops and applies their in-house software, the potential flow code νShallo, the viscous flow code FreSCo+ and the propeller panel code QCM. νShallo is typically used for early design hull form optimization and FreSCo+ for detailed flow predictions according to model basin standards. QCM is used for the prediction of the propeller open water characteristics or coupled with FreSCo+ for the analysis of hull-propulsor interaction.

Ship performance assessments and calm water speed-power predictions are performed based on accurate resistance and propulsion calculations, using fully resolved or potential flow propeller models as well as roughness corrections methods in model or full scale, including consideration of the free surface and dynamic trim and sinkage. In holistic vessel optimizations tasks the different numerical tools available at HSVA, are used to enhance the vessels characteristics with focus on resistance, propulsion, powering, sea keeping, maneuvering and ice performance.

For more information please contact Henning Grashorn

Various tools based on empirical data, potential and viscous flow theory are available to predict the motions and the wave added resistance for vessels and offshore structures in irregular and regular waves. Non-linear effects like parametric-rolling, slamming and sloshing in (moon-) pools can be addressed and roll damping devices like bilge keels, damping tanks and stabilizer-fins can be considered in the calculations.  

Numerical methods can be applied in the frequency domain, e.g. for obtaining data for fast statistical evaluation, or simulations in the time domain enable the assessment of non-linear phenomena.

For more information please contact Jan Lassen or YongPyo Hong.

For the assessment of the maneuvering capability and course-stability of vessels various manoeuvers like berthing, turning circle, zig-zag or crash stop can directly simulated in time domain or on the basis of viscous hydrodynamic coefficients in a simulator-tool. The simulator-tool also affords to verify dynamic-positioning (DP) requirements.

For more information please contact Jan Lassen or Yan Xing-Kaeding

Beyond the traditional hydrodynamic applications, HSVA has extended its portfolio towards the aerodynamics of vessels and offshore structures with respect to wind loads, passenger comfort on open decks, exhaust gas dispersion and helicopter operational conditions (CAP 437), following the overall goal of energy-saving and ensuring safety in operation.

For more information please contact Niklas Kühl

HSVA is developing a discrete-element method (DEM) for the simulation of vessels and offshore structures in ice ridges and brash ice. Several ice-breaking mechanisms are already implemented and it’s planned to extend the tool for the prediction of broken and managed ice in the near future.

For more information please contact Nils Reimer