Trajectories for simulated diffusion MRI of turbulent flow in porous media

Dataset contains Lagrangian position and velocity data for a turbulent flow in porous medium. The data consist of 100,940 points over 0.17 s in increments of 1e-4 s. Data are stored in MATLAB .mat format. - trajectories*.mat: x,y,z are position data, u,v,w are velocity data. Each file has ~14000 individual trajectories. Separate files for ease of upload/download. MATLAB scripts are included to process the data via calculation of mean squared displacement (calcMSD.m) and velocity autocorrelation (calcVACF.m). An additional script simulates multidimensional diffusion MRI experiments on the trajectories (simMRI.m). This script produces plots of the phase distribution kurtosis and Stejskal-Tanner plots to illustrate gradient waveform conditions (duration, number of modulations, anisotropy) where the Gaussian phase approximation holds. Phase variance is normalised by the variance for free diffusion (coefficient determined from the MSD) under the same gradient waveform. These data are stored in the "freeDiffProcs*.mat" files for three encoding anisotropy cases.