Correlation Between the Size Characteristics of the Wall Jet and the Dynamics of the Unsteady Film Formed After the Impingement of an Unsteady Two-Phase Jet,
Abstract
The consequences of the oblique impingement of an unsteady two-phase jet on heated surfaces have been studied with and at an angle of incidence alpha=20 onto a hot plate at a surface temperature of 240 deg C. Frequency modulated signal analysis, a newly developed optical technique, was used together with phase Doppler velocimetry to identify the mechanism of the droplet generation by the material torn or ejected from the liquid film deposited on the wall, and offered the prospect of a more detailed study of the thin film dynamics than has previously been possible. The results show that atomisation of the film with the impingement of the inflowing two-phase jet led to a new size class with larger droplets which tended to stay close to the wall within the impingement region with small vertical velocities. The secondary atomisation with direct wall contact, thus, caused strong correlation between the variation of the unsteady film thickness and the droplet size of the two-phase wall jet. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 23, 1992
- Accession Number
- ADP009049
Entities
People
- I. B. Oezdemir
Organizations
- Imperial College London