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Problem Specification

Overview

Option #1:

This tutorial considers the deformation due to aerodynamic loading of a wind turbine blade by performing a steady-state 1-way FSI (Fluid-Structure Interaction) analysis. Part 1 of the tutorial uses ANSYS Fluent to develop the aerodynamics loading on the blade. In part 2, the pressures on the wetted areas of the blade are passed as pressure load to ANSYS Mechanical which performs the Computational Structural Mechanics (CSM) to determine stresses and deformations on the blade. 

The blade is 42.3 meters long and starts with a cylindrical shape at the root and then transitions to the airfoils S818, S825 and S826 for the root, body and tip, respectively. This blade also has a varying pitch to vary as a function of radius, which gives giving it a twist and the pitch angle at the blade tip is 4 degrees. This blade was created to be similar in size to a GE 1.5X 5XLE turbine. For more information on the dimension characteristics of this blade, please see this M.Eng report (note that model in the present tutorial has an additional 2 meter cylindrical extension at the root to make it more realistic). The blade is made out of an orthotropic composite material, it has a varying thickness and it also has a spar along inside the length of the blade for structural rigidity. These are further described in Part 2 of the tutorial.

This blade is spinning at an angular velocity of -2.22 rad/s with respect to the incoming wind (the blade is thus spinning clockwise like most real wind turbines). The upstream wind speed (or should we say the free stream velocity?) is 12 m/s (a typical rated wind speed for a turbine this size) (say something about it being turbulent?. This blade therefore has a tip speed ratio, which is the ratio of tip velocity to incoming wind, of 8 (also a typical value). 

Part 1

In this section of the tutorial, the blade geometry is imported, a mesh is created around the blade and Fluent is then used to find the aerodynamics loading on the blade. Here 's some is more information about the set-up. 

Solver: Pressure-based

Viscous model: k-omega SST

Fluid: Air at standard conditions (15 degree celcius). It has 's density of is 1.225 kg/m^3 and it's viscosity of 1is 1.7894e-05 kg/m*s

The boundary conditions for this problem are as follow.

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Cell zone condition: Moving frame of reference (with the blade).

Main Boundary conditions:

              Inlet: Velocity of 12 m/s with turbulent viscosity of 5% and turbulent viscosity ratio of 10. 

              Outlet: Gauge pressure of zero. 

              Blade: Wall

Operating conditions: Pressure at 1 atm.

 Finally, periodics are used to allow the visualization of results for three blades.Inlet: 

Go to Step 1: Pre-Analysis & Start-Up

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