This LPT_ASL_readme.txt file was updated on 2024-06-12 by Nick Conlin


GENERAL INFORMATION

1. Title of Dataset: 
	Data for "Lagrangian Particle Tracking in the Atmospheric Surface Layer"

2. Author Information
	Name: Nick Conlin
	Institution: Princeton University		
	Email: nconlin@princeton.edu

3. Date of data collection <YYYY-MM-DD>: 
	2023-10-09

4. Geographic location of data collection: 
	Island Beach State Park, NJ, USA

5. Information about funding sources that supported the collection of the data: 
	This work was partially funded by the National
	Science Foundation (NSF) under award number 2132727 as well as the Gordon and
	Betty Moore Foundation under grant number GBMF11572. N Conlin was partially
	supported by the New Jersey Economic Development Authority (NJEDA) Wind
	Institute Fellowship. NJ Wei was supported by the Andlinger Center for Energy and
	the Environment Distinguished Postdoctoral Fellowship


SHARING/ACCESS INFORMATION

1. Licenses/restrictions placed on the data: 
	CC-BY 4.0

2. Links to publications that cite or use the data: 
	Conlin, Nicholas, et al. "Lagrangian Particle Tracking in the Atmospheric Surface Layer." Meas. Sci. Technol., 11 June 2024, doi:10.1088/1361-6501/ad56ac.

DATA & FILE OVERVIEW

1. File List: 
	track_data.txt: three dimensional trajectories of helium filled soap bubbles 
	including position, velocity, and track index. 

METHODOLOGICAL INFORMATION

1. Description of methods used for collection/generation of data: 
	Trajectory data was collected using a custom particle tracking system detailed in
	"Lagrangian Particle Tracking in the Atmospheric Surface Layer." A field campaign
	was conducted at Island Beach State Park in New Jersey. Helium filled soap
	bubbles were released (~20 m) upstream of a 8m x 8m x 4m measurement domain. Four Canon R5 cameras operating at 4K resolution
	and 120 Hz imaged the bubbles. Camera calibration was performed with a wand wave technique. A Direct
	Linear Transform (DLT) model for each camera was used with no distortion corrections.  	
	
2. Methods for processing the data: 
	Particles were 	identified in each camera and then triangulated to form a point cloud. Triangulation is performed using the 
	ray-traversal algorithm of Bourgoin and Huisman 2020 (doi: 10.1063/5.0009357).
	Tracking is performed using a 2-frame kinematic prediction. Velocities are computed by
	convolving trajectories with a Gaussian kernel with a 3 frame width. See publication for further details. 


DATA-SPECIFIC INFORMATION FOR: track_data.txt

1. Number of variables: 8

2. Variable List: 
	x: streamwise particle position in meters, the x origin is at the center of the measurement domain
	y: lateral particle position in meters, the y origin is at the center of the measurement domain
	z: vertical particle position in meters, the z origin is on the ground
	u: streamwise velocity in meters per second
	v: lateral velocity in meters per second
	w: vertical velocity in meters per second
	frame: video frame number (unitless)
	track index: number identifying which trajectory this particle belongs to (unitless)