We investigate the unsteady heat transfer in harmonically excited liquid-film flows falling under the action of gravity over an electrically-heated inclined glass-substrate, by simultaneous application of planar laser-induced fluorescence (PLIF), particle image and particle tracking velocimetry (PIV/PTV), and infrared thermography (IR). These non-intrusive optical techniques allow us to recover detailed information on the film-height ( PLIF), the velocity field underneath the wavy interface (PIV/PTV), and the free-surface (gas-liquid interface) temperature (IR), with high spatial and temporal resolution. Based on these data and knowledge of the applied heat-flux and substrate temperature at the measurement location, the local and instantaneous heat-transfer coefficient (HTC) is also evaluated. Preliminary results from select flow-regions suggest significant deviations compared to expectations from equivalent steady flows.
- Heat Transfer Division
Application of Laser-Induced Fluorescence, Particle Velocimetry and Infrared Thermography to Heated Falling-Film Flows
Charogiannis, A, & Markides, CN. "Application of Laser-Induced Fluorescence, Particle Velocimetry and Infrared Thermography to Heated Falling-Film Flows." Proceedings of the ASME 2017 Heat Transfer Summer Conference. Volume 2: Heat Transfer Equipment; Heat Transfer in Multiphase Systems; Heat Transfer Under Extreme Conditions; Nanoscale Transport Phenomena; Theory and Fundamental Research in Heat Transfer; Thermophysical Properties; Transport Phenomena in Materials Processing and Manufacturing. Bellevue, Washington, USA. July 9–12, 2017. V002T11A015. ASME. https://doi.org/10.1115/HT2017-5081
Download citation file: