Dataset for "Role of Friction on the Formation of Confined Granular Structures"
Description
In this dataset, you will find information concerning experiments described in the article entitled “Role of Friction on the Formation of Confined Granular Structures”. It contains data on PTFE particles (see the section "related links" to access ABS data) for: 1. scripts for replicating the image processing and post-processing. There are examples of figures concerning experiments carried out at the fluidized bed bench; 2. data files from the profilometer, the rugosity measurements, and rheometer measurements; 3. Files for plotting figures in Gnuplot with PostScript terminal.
Files
Steps to reproduce
Before reproducing the steps below, ensure that your system has the minimum requisites to run image processing. The steps below assume that you are using a Linux system 2018.04 or later distributions with MATLAB 2020 and the image toolbox. 1. The Fluidized bed image processing and post-processing (a) load the functions of image processing to the system path, running the "habilitar_funcao.m" MATLAB function and run a terminal on the experiments folder; (b) split the video in frames, and create "Frames/" folder with "mkdir" command. Then, use the "ffmpeg" application using the command "ffmpeg -i [video_name] image%06d.png", where "[video_name]" is the name of the target video. (c) set the parameters of image processing with "set_prmV2_C1.m" function. To run each block of the file press Ctrl+Enter to see a preview of the result of the processing; (d) apply the defined parameters at each image with "detectar_objV2_C1.m" function; (e) apply the macroscopic processing using the set of functions presented in "sources/phi_float_processing.m" file. (f) apply the particle tracking and cinematic analysis by using the set of functions presented in the file "sources/particle_trackingV1.m" file. 2. Profilometer To reproduce the results of these measurements, open the .data files in the "rheometer_and_profilometer_data/Profilometer" folder in an Dektak 150 profilometer or perform the measurements in the the profilometer you desire with the parameters in "ABS_particle2.csv" and/or "PTFE_particle2.csv". The data is adjusted using a cylindrical transformation to avoid the influence of the curvature of the sphere. 3. Rheometer To perform friction experiments on a MCR 502 Anton Paar Rheometer, follow the steps: (a) dispose of ur sample properly and put a drop of water at the surface. (b) set the experiment imposing a normal between 0.2 to 5 Newtons for 30 seconds; (c) set the time step of the experiments and total duration of the second part of the experiment to fit a constant angular displacement of the probe cell; (d) then, set the experiments applying a constant tangential velocity maintaining the normal force and measuring the normal force, the torque, and the tangential velocity; (e) when the experiment is set properly, run the experiment; (f) at the end of the experiment, displace the probe cell until there is no normal force, and restart the procedure as many times as necessary to cover the range of tangential velocities you need; (g) calculate the friction factor for each time step by dividing the tangential force (the torque divided by radius relative to the center line of probe cell and the sample) by the normal force, then take the average between all time steeps.
Institutions
Categories
Funding
Centre National de la Recherche Scientifique
Fundação de Amparo à Pesquisa do Estado de São Paulo
2024/02440-2