Droplet characteristics as a function of experimental parameters in electrospray deposition

Hong, Jung Goo1 ; Kim, Ji Yeop1 ; Sang, Ji Lee1 ; Kim, Jun Yeop1

Research facility: Kyungpook National University

Published Jan 25, 2024 on Dryad. https://doi.org/10.5061/dryad.mcvdnck73

Data files

Jan 25, 2024 version files 4.83 MB

droplet_size.xlsx

56.29 KB
NTR_OD_ratio_x_rnratio_y_smd_2023-09-27.opj

4.70 MB
Organizing_Experimental_Expressions_2024.01.24.xlsx

70.30 KB
README.md

4.26 KB

Abstract

In this study, the atomization mode and droplet size of an electrostatic atomization system and a system with a ring electrode were compared. The parameters of the ring electrode, namely the outer diameter of the nozzle, nozzle-to-ring distance, and applied voltage, were used to determine the droplet size and atomization characteristics. In addition, the droplet size was compared with those calculated using existing theoretical equations, and the Sauter mean diameter (SMD) of ethanol = a(1 + applied ring/nozzle voltage (RNV))b and SMD of distilled water = a(1 + RNV)b were calculated. These SMDs can be used for determining the nozzle-to-ring/outer diameter ratios up to a maximum range of 10.

README: Droplet characteristics as a function of experimental parameters in electrospray on deposition process

https://doi.org/10.5061/dryad.mcvdnck73+

README DESCRIPTION

In this experiment, the droplet size equation using experimental parameters is different from the existing droplet size equation using only fluid properties, and the experimental variables are divided into nozzle diameter, nozzle and ring distance, ring diameter, and ring voltage, and the experiment was conducted using ethanol and distilled water, two representative solvents most often used in electrostatic atomization. The flow rate was fixed at 1.5 ml/h to derive the droplet size equation based on the experimental parameters.

For the applied voltage, the applied voltage output from the HVPS was saved in excel in real time for the experiment. For droplet size and distribution, we used spray tech equipment using marlvern's MIE scattering technique to receive data on the DAQ board in real time. For the droplet size expression, ORIGIN PRO 16 was used to obtain the droplet size expression using the function function.

All files are used to create a datasheet in Excel.

To check the atomization mode droplet size, we created a data sheet using excel and obtained it in real time, and for the droplet size expression, we created an expression using the function function of Origin pro 16.

There are three main files: droplet_size, Organizing_Experimental_Expressions, and NTR_OD_ratio_x_rnratio_y_smd.

The nozzle gage in the droplet_size file uses 13,14,17,21,27 stainless steel nozzles for the nozzle diameter, and hollow rings for the ring diameter, and the experiments were conducted with rings with inner diameters of 15,20,30,40mm. NTR checked the effect of the electric field on the distance between the nozzle and the ring with -20,-10,0,5,10,20, and for the ring voltage, 0,1,3,5,7 kV was applied to check the intensity of the electric field by the applied voltage of the ring. The data of SMD, SMD standard deviation, and RSD of ethanol and distilled water are shown from cell F to cell J. N/A is used to distinguish between experimental conditions and results.

The file Organizing_Experimental_Expressions is a graph showing the slope correlation of water and distilled water as a function of rain with Pearson correlation coefficient as a function of nozzle to substrate distance and nozzle outer diameter, the experimental parameters that have the greatest influence on droplet size. Ethanol flowrate graph and Distilled flowrate graph showing the droplet size equation according to the experimental conditions at a flow rate of 1.5 ml/h. For raw data fitting, the equation is expressed using the power function using the NTR/OD ratio. For the equation, it is expressed as pow2p2(y=a(1+x)^b, and the values of r^2,a,b are the values of the above equation. In the case of the R^2 sheet, as a sheet to check the reliability of the data, the value according to the range was represented as range, and the value up to R^2 (rang 1~4) was represented through the value, and the value above 0.6 was judged to be reliable.

ID(mm) = nozzle inner diameter, OD(mm) = nozzle outer diameter, NTR(mm)=nozzle to ring, R/N ratio=Ring voltage/nozzle voltage, ring d/od= nozzle outer diameter/ring diameter, ntr/od ratio=nozzle to ring distance/nozzle outer diameter, n/a =All N/A data represent blank spaces and were used to separate cells for experimental condition values and outcome values.

Sharing/Access information

All experiments were conducted by ourselves

Financial support

This work was supported by the Human Resources Program in Energy Technology of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and was granted financial resources from the Ministry of Trade, Industry & Energy, Republic of Korea (No. 20204010600060).