Influence of Wall Deformation Structure on the Liquid Film Flow Behavior Under Turbulent Conditions

ABSTRACT To explore the influence of typical wall deformation structure in the scrubbing‐cooling tube on the liquid film, this paper studied the liquid film flow behavior on the riblet walls with representative riblet radii and compared them with the flat wall. Under different liquid film Reynolds numbers ( Re l = 8.3 × 10 3 ~ 3.14 × 10 4 ), the liquid film velocity and thickness on different wall conditions were measured by ultrasonic Doppler velocimetry (UDV). The results show that the riblet wall will cause reflux of the liquid, which plays a thickening effect and slows down the thinning of the liquid film. The riblet wall changes the force distribution and extends the residence time of the liquid film. Combined with average liquid film thickness data on different wall surfaces, a prediction model of average liquid film thickness on the riblet wall can be established, with an error within ±20%.