virocon.predefined module

Common joint model structure are predefined in this module.

virocon.predefined.get_DNVGL_Hs_Tz()[source]

Get DNVGL significant wave height and wave period model.

Get the descriptions necessary to create th significant wave height and wave period model as defined in DNVGL 1 in section 3.6.3.

Returns

  • dist_descriptions (list of dict) – List of dictionaries containing the dist descriptions for each dimension. Can be used to create a GlobalHierarchicalModel.

  • fit_descriptions (None) – Default fit is used so None is returned. Can be passed to fit function of GlobalHierarchicalModel.

  • semantics (dict) – Dictionary with a semantic description of the model. Can be passed to plot functions.

References

1

DNV GL (2017). Recommended practice DNVGL-RP-C205: Environmental conditions and environmental loads.

virocon.predefined.get_DNVGL_Hs_U()[source]

Get DNVGL significant wave height and wind speed model.

Get the descriptions necessary to create the significant wave height and wind speed model as defined in DNVGL 2 in section 3.6.4.

Returns

  • dist_descriptions (list of dict) – List of dictionaries containing the dist descriptions for each dimension. Can be used to create a GlobalHierarchicalModel.

  • fit_descriptions (None) – Default fit is used so None is returned. Can be passed to fit function of GlobalHierarchicalModel.

  • semantics (dict) – Dictionary with a semantic description of the model. Can be passed to plot functions.

References

2

DNV GL (2017). Recommended practice DNVGL-RP-C205: Environmental conditions and environmental loads.

virocon.predefined.get_Nonzero_EW_Hs_S()[source]

Get the non-zero EW sea state model.

Get the descriptions necessary to create the significant wave height - steepness model that is an adaptation of Windmeier’s EW model [5]_. Both, Hs and Steepness follow an exponentiated Weibull distribution.

Compared to Windmeier’s EW model, this model has a dependence function for scale that evaluates to scale > 0 at hs = 0 m . The dependence function reads: shift + a * (1 - np.exp(-b * hs))

Because the model is defined in Hs-steepness space it must be transformed to Hs-Tz for contour calculation.

This model was introduced in the virocon software, there is research paper describing it.

Returns

  • dist_descriptions (list of dict) – List of dictionaries containing the dist descriptions for each dimension. Can be used to create a GlobalHierarchicalModel.

  • fit_descriptions (None) – Default fit is used so None is returned. Can be passed to fit function of GlobalHierarchicalModel.

  • semantics (dict) – Dictionary with a semantic description of the model. Can be passed to plot functions.

  • transformations (dict)

References

5

Windmeier, K.-L. (2022). Modeling the statistical distribution of sea state

parameters [Master Thesis, University of Bremen]. https://doi.org/10.26092/elib/2181

virocon.predefined.get_OMAE2020_Hs_Tz()[source]

Get OMAE2020 significant wave height and wave period model.

Get the descriptions necessary to create the significant wave height and wave period model as described by Haselsteiner et al. 3.

Returns

  • dist_descriptions (list of dict) – List of dictionaries containing the dist descriptions for each dimension. Can be used to create a GlobalHierarchicalModel.

  • fit_descriptions (list of dict) – List of dictionaries containing the fit description for each dimension. Can be passed to fit function of GlobalHierarchicalModel.

  • semantics (dict) – Dictionary with a semantic description of the model. Can be passed to plot functions.

References

3

Haselsteiner, A.F.; Sander, A.; Ohlendorf, J.H.; Thoben, K.D. (2020) Global hierarchical models for wind and wave contours: Physical interpretations of the dependence functions. OMAE 2020, Fort Lauderdale, USA. Proceedings of the 39th International Conference on Ocean, Offshore and Arctic Engineering.

virocon.predefined.get_OMAE2020_V_Hs()[source]

Get OMAE2020 wind speed and significant wave height model.

Get the descriptions necessary to create the wind speed and significant wave height model as described by Haselsteiner et al. 4.

Returns

  • dist_descriptions (list of dict) – List of dictionaries containing the dist descriptions for each dimension. Can be used to create a GlobalHierarchicalModel.

  • fit_descriptions (list of dict) – List of dictionaries containing the fit description for each dimension. Can be passed to fit function of GlobalHierarchicalModel.

  • semantics (dict) – Dictionary with a semantic description of the model. Can be passed to plot functions.

References

4

Haselsteiner, A.F.; Sander, A.; Ohlendorf, J.H.; Thoben, K.D. (2020) Global hierarchical models for wind and wave contours: Physical interpretations of the dependence functions. OMAE 2020, Fort Lauderdale, USA. Proceedings of the 39th International Conference on Ocean, Offshore and Arctic Engineering.

virocon.predefined.get_Windmeier_EW_Hs_S()[source]

Get Windmeier’s EW sea state model.

Get the descriptions necessary to create the significant wave height - steepness model that was proposed by Windmeier [5]_. Both, Hs and Steepness follow an exponentiated Weibull distribution.

Because the model is defined in Hs-steepness space it must be transformed to Hs-Tz for contour calculation.

Returns

  • dist_descriptions (list of dict) – List of dictionaries containing the dist descriptions for each dimension. Can be used to create a GlobalHierarchicalModel.

  • fit_descriptions (None) – Default fit is used so None is returned. Can be passed to fit function of GlobalHierarchicalModel.

  • semantics (dict) – Dictionary with a semantic description of the model. Can be passed to plot functions.

  • transformations (dict)

References

5

Windmeier, K.-L. (2022). Modeling the statistical distribution of sea state

parameters [Master Thesis, University of Bremen]. https://doi.org/10.26092/elib/2181