|Source||FDMP: Fluid Dynamics & Materials Processing, Vol. 10, No. 1, pp. 37-61, 2014|
|Download||Full length paper in PDF format. Size = 1,701,933 bytes|
|Keywords||spray; spray impact; wall film; film thickness; Phase Doppler.|
This study presents a combined experimental and theoretical investigation on the formation and spreading of a liquid film on a flat and rigid wall due to spray impact. A dual-mode phase Doppler instrument is used to characterise the spray while the average film thickness is measured using a high-speed CCD camera. The experimental results are complemented with theoretical expressions derived under the assumption that the spray is stationary. A new model for the prediction of the average wall film thickness is formulated taking into account the mean Reynolds number of the impacting drops, the flux density of the impacting droplets, and the average drop diameter. The theoretically determined average film thickness exhibits a good agreement with the measured data when the film can be considered thin.