Unfrozen skewed turbulence for wind loading on structures

Synthetic turbulence generation in 3D for yawed flow simulation with possible relaxation of Taylor's hypothesis of frozen turbulence

Unfrozen skewed turbulence for wind loading on structures

The present repository includes the Matlab source code used to generate skewed turbulence for wind loading on structures, as presented in [1]. Topic of interests are: wind engineering, structural dynamics, random processes, structural analysis, boundary layer meteorology, atmospheric science (turbulence)

Content

The repository contains:

• A Matlab livescript Documentation.mlx showing the case of a Diamond geometry

• A Matlab livescript regular_grid.mlx showing the case of a regulat grid and data are saved in a format similar to windSimFast

• The Matlab function windSim4D, which generate the wind field on a 4D grid (3 spatial dimensions, one temporal one)

• The functions getTargetSpectra, which computes the 1-point auto and cross-spectral densities used as input

• The functions getRegularGrid, which setup the regular grid for the Example case 2.

• The function getSamplingPara that provides the time and frequency vector for the initialisation of the simulation

• The function WindToBridgeBase, which projects the horizontal wind field (u,v) onto the structural elements. This leads to a wind field (vx0,vy0). The name of the function "WindToBridgeBase" comes from the fact that it was first applied for the case of a horizontal bridge deck.

• The function PlotWindProjection, which shows the wind speed components (u,v) and (ux0,vy0) in the wind-based coordinate system and the structure-based coorindate system

• The function frictionVelocity, which estimate the friction velocity from the simulated velocity histories.

• The function plotSpectra, which compares the target and simulated velocity spectra.

• The function coherence, which provides the co-coherence and quad-coherence estimates.

• The functions plotCoh_diamond and plotQuadCoh_diamond, which are used in the tutorial only and compare the target and estimated co-coherence and quad-coherence, respectively

• The function ** nearestneighbour.m** [2] This is the first version of the submission. Some bugs may still be present. Any question or comment is welcome

References

[1] Cheynet E, Daniotti N, Bogunović Jakobsen J, Snæbjörnsson J, Wang J. Unfrozen Skewed Turbulence for Wind Loading on Structures. Applied Sciences. 2022; 12(19):9537. https://doi.org/10.3390/app12199537 [2] Richard Brown (2023). nearestneighbour.m (https://www.mathworks.com/matlabcentral/fileexchange/12574-nearestneighbour-m), MATLAB Central File Exchange. Retrieved June 9, 2023.