Load application method for shell finite element model of wind turbine blade

Abstract

It is common to dissociate load computation from structural analysis when carrying out a numerical assessment of a wind turbine blade. Loads are usually computed using a multiphysics and multibody beam finite element model of the whole turbine, whereas detailed structural analysis is managed using shell finite element models. This raises the issue of the application of the loads extracted from the beam finite element model at one node for each section and transposed into the shell finite element model. After presenting the methods found in the literature, a new method is proposed. This takes into account the physical consistency of loads: aerodynamic loads are applied as pressure on the blade surface, and inertial loads are applied as body loads. Corrections imposed by pressure and body load computation in order to match loads from the beam finite element model are proposed and a comparison with two other methods is discussed.

On the wind turbine blade loads from an aeroelastic simulation and their transfer to a three-dimensional finite element model of the blade

“…A way of doing that is to apply a concentrated force at the nearest node from each blade element center corresponding to the aerodynamic force at this blade element (see for example a report by Griffith and Ashwill, 2011). Another way is to try to reproduce the pressure field on the blade surface using the blade airfoil properties and the angles of attack computed by the aerodynamic analysis tool (see for example the work of Caous et al, 2018; Knill, 2005).…”