Warning

In our use of FloatingSE, we have not been able to obtain conceptual platform geoemtry results that we trust are valid and worth pursuing further. This may be due to a fundamental error in the formulation and implementation of FloatingSE. It may also be due to the inherent limitations in using steady-state or quasi-static analysis methods to tackle a problem that is driven by its dynamic nature and dynamic loads. NREL currently advises against reliance on FloatingSE. Instead, we are developing a multifidelity floating turbine and platform design capability in the Wind Energy with Integrated Servo-control (WEIS) project.

Introduction

The complexity of the physics, economics, logistics, and operation of a floating offshore wind turbine makes it well suited to systems-focused solutions. FloatingSE is the floating substructure cost and sizing module for the WISDEM.

This document serves as both a User Manual and Theory Guide for FloatingSE. FloatingSE can be executed as a stand-alone module or coupled to the rest of the turbine through the WISDEM glue code. An overview of the package contents is below and substructure geometry parameterization in Section Geometry. With this foundation, the underlying theory of FloatingSE’s methodology is explained in Section Theory. This helps to understand the analysis execution flow described in Section Execution and the setup of design variables and constraints for optimization problems in Section Optimization.

Package Files

The files that comprise the FloatingSE package are listed in Table 3. Each file has a corresponding unit test file in the test_floatingse directory.

Table 3 File contents of the FloatingSE module.

File Name		Description
floating.py		Top level FloatingSE OpenMDAO Group
column.py		Components calculating mass, buoyancy, and static stability of vertical frustum columns
loading.py		Components for Frame3DD analysis of structure, mass summation, and displacement
map_mooring.py		Mooring analysis using pyMAP module
substructure.py		Final buoyancyand stability checks of the substructure
visualize.py		Standalone script that uses MayaVI to view substructure geometry