READ ME File For 'Dataset title' Dataset DOI: 10.5258/SOTON/D2406 ReadMe Author: SAMVIR THANDI, University of Southampton ORCID ID: 0000-0002-5327-7543 This dataset supports the thesis entitled "The effect of a recessed liquid jet on the performance of coaxial air-assist atomisers" AWARDED BY: University of Southampton DATE OF AWARD: 2022 DESCRIPTION OF THE DATA This dataset contains: Data relating to three chapters in the thesis: Qualitative studies, PDIA Laser imaging experiments, and High-speed camera experiments. QUALITATIVE IMAGES The qualitative studies are split up into folders of the 12 experimental cases that are outlined in the thesis. The cases are as follows: Case 1: Re=1551, We=5.22 Case 2: Re=1551, We=11.6 Case 3: Re=1551, We=22.9 Case 4: Re=1551, We=52.7 Case 5: Re=2940, We=5.22 Case 6: Re=2940, We=11.6 Case 7: Re=2940, We=22.9 Case 8: Re=2940, We=52.7 Case 9: Re=6444, We=5.22 Case 10: Re=6444, We=11.6 Case 11: Re=6444, We=22.9 Case 12: Re=6444, We=52.7 Where Re refers to Reynolds number and We refers to Weber number. In each folder there are between 3-4 images, each one relating to a different recess ratio which is identified in the file name. For example RR_1-5 refers to a recess ratio of 1.5 Additionally the images from the CCD camera are also included and these are split up into images from the 2mm liquid jet diameter nozzle and the 3mm liquid jet diameter nozzle. The 2mm experiments were conducted at Re=5250, and We=24. The 3mm experiments were conducted at Re=7950, and We=23 LASER DATA The laser data is split up into folders of axial position where z-d=50 refers to an axial location downstream of z/d=50. In each of these folders there are further folders indicating the Weber number of the experiments for example We=18-34 refers to We=18.34, a dash is used to replace decimal points where necessary to maintain file compatibility across operating systems and to avoid confusion with file extensions. Within each of these Weber number folders contains each recess ratio that was measured, for example RR=1-5 refers to a recess ratio of RR=1.5 In each folder there are four files. 'full frame data' is the per frame individual file data containing all the drops that have been identify and the corresponding drop size, velocity, angle, and shape factor. 'Statistical summary' is a summary report text file which provides the average drop diameters, minimum and maximum diameters, as well as other statistical information and experimental set up information. It also contains a table of drop diameter bins and a velocity size correlation. There are also two accompanying pdf files which are generated by the VisiSize software. The VisiSize report is a statistical overview, information about the performance of the system, system settings, and a summary of the data. VisiSize Full Page Plots contains diameter plots, velocity plots, and velocity size-correlation plots which are full sized. HIGH SPEED CAMERA DATA The high speed camera data is split up into multiple folders. Edge results contains csv files corresponding to the location of the jet edges. This is split into Reynolds numbers, Weber numbers, and recess ratios. The final number in each csv file corresponds to the pixel position downstream at which the edges were measured. For example a file ending in _50 is the edge positions at an axial location 50 pixels downstream from the top of the image. The total height of all images was 1024 pixels. The fft folder contains the Fourier transforms of the edges using the method described in the thesis. This is split up into the Reynolds numbers, Weber numbers, and recess ratio. The csv file contains the frequency, initial diameter a0 value, the diameter growth rates, the curve fit error for this diameter growth rate, the centroid initial a0 value, the centroid growth rates, and the error in the curve fit for this particular frequency. Morozumi replication contains the edges and Fourier transform for the experiments that replicated the conditions of the Morozumi and Fukai paper. Python codes contains the Python scripts that were used to generate this data. The high speed camera video files were processed using 'highspeed_image_processing.py' where the image processing method was used, this produced the edges files that are provided in this dataset. The second python script 'highspeed_fft.py' is where the main code lies, the function 'growth_rate' creates a file which contains the Fourier transform for the growth rates of the axisymmetric and asymmetric instability. The final script 'plot_processing.py' contains functions to plot the data that has been generated. This data was taken using a Photo SA-X2 camera with 128GB onboard memory. It was backlit with a GVM 672S LED light panel. Due to the large size of the high speed camera data the original video files are not provided, however the extracted edges files are provided which allows the user to produce Fourier transforms utilising the method described in the thesis by using the accompanying python scripts. Reference data contains extracted data from the paper by Morozumi and Fukai. Threshold testing is a set of experiments that determined the effect of the threshold on the results. Date of data collection: 2019-2020 Information about geographic location of data collection: Licence: CC BY Related projects/Funders: EPSRC Kelda Showers Related publication: Date that the file was created: October, 2022