The relationship between ‘microscopic’ velocity field and ‘macroscopic’ outcomes of liquid droplet impact on wall-films is not yet fully understood. This article reports a preliminary experimental investigation to measure the velocity field within wall-film when a droplet impacts on it, using micro-Particle Image Velocimetry (μ-PIV). The challenges associated with measuring the velocity field within the wall-film are outlined. In this context, the limitations of the traditional μ-PIV technique are discussed, leading to the adoption of high-speed μ-PIV as the suitable technique for measuring the spatio-temporal evolution of velocity within wall-film. The salient features of the high-speed μ-PIV set-up are discussed. Further, results from preliminary experimental investigations on water droplet impacting on water wall-film at moderate impact velocities are presented. It is seen that the current high-speed μ-PIV set-up can be used to obtain reliable measurements of in-plane radial velocity, V, at ‘intermediate’ values of radial, r, and temporal, t, coordinates. Within the measurement range of the current set-up, it is observed that V scales with r and t as V ∝ r/t, which is similar to that reported in literature based on analytical considerations. The limitations of the current set-up, and the requirements for further experiments and validation are highlighted.

(2020). On the Measurement of Velocity Field Within Wall-Film During Droplet Impact on It Using High-Speed Micro-PIV . Retrieved from http://hdl.handle.net/10446/158149

On the Measurement of Velocity Field Within Wall-Film During Droplet Impact on It Using High-Speed Micro-PIV

Cossali, G. E.;Weigand, B.
2020

Abstract

The relationship between ‘microscopic’ velocity field and ‘macroscopic’ outcomes of liquid droplet impact on wall-films is not yet fully understood. This article reports a preliminary experimental investigation to measure the velocity field within wall-film when a droplet impacts on it, using micro-Particle Image Velocimetry (μ-PIV). The challenges associated with measuring the velocity field within the wall-film are outlined. In this context, the limitations of the traditional μ-PIV technique are discussed, leading to the adoption of high-speed μ-PIV as the suitable technique for measuring the spatio-temporal evolution of velocity within wall-film. The salient features of the high-speed μ-PIV set-up are discussed. Further, results from preliminary experimental investigations on water droplet impacting on water wall-film at moderate impact velocities are presented. It is seen that the current high-speed μ-PIV set-up can be used to obtain reliable measurements of in-plane radial velocity, V, at ‘intermediate’ values of radial, r, and temporal, t, coordinates. Within the measurement range of the current set-up, it is observed that V scales with r and t as V ∝ r/t, which is similar to that reported in literature based on analytical considerations. The limitations of the current set-up, and the requirements for further experiments and validation are highlighted.
Vaikuntanathan, V.; Bernard, R.; Lamanna, G.; Cossali, G. E.; Weigand, B.
File allegato/i alla scheda:
File Dimensione del file Formato  
DROPIT_HSmPIV.pdf

Solo gestori di archivio

Versione: publisher's version - versione editoriale
Licenza: Licenza default Aisberg
Dimensione del file 652.31 kB
Formato Adobe PDF
652.31 kB Adobe PDF   Visualizza/Apri
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

Aisberg ©2008 Servizi bibliotecari, Università degli studi di Bergamo | Terms of use/Condizioni di utilizzo

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10446/158149
Citazioni
  • Scopus 0
  • ???jsp.display-item.citation.isi??? ND
social impact