Numerous engineering applications involve dropwise cooling of hot solid surfaces, which has become a major research task for both academia and industry. This work focuses on single-phase evaporation regime, proposing a fully non-intrusive technique to measure the solid/liquid interface temperature and a simple numerical code to evaluate heat flux. A comparison between a single droplet and two sequentially released droplets is presented. Infrared thermography was used to measure the transient contact temperature of droplets released onto a BaF2 disk coated by a black-painted layer; interface temperature was measured from below through the solid body. The total released volume of water was kept constant; droplet Weber number was lower than 70; the initial surface temperature was nominally 80 °C. A self-developed numerical code was developed to simulate the evaporation mechanism under single-phase evaporation regime. The threedimensional energy diffusion equation describing the transient within both the liquid and the solid phase was discretized by the finite-volume method. The model aims at ultimately predicting the heat-flux distribution at the solid/liquid interface. Flux distribution was obtained for both the single-and the two-droplet case; moreover, heat flux was evaluated all over the sampling region. Validation was performed as a comparison between numerical and experimental temperature datasets at the substrate surface, showing very good agreement for both the cases, especially for the wetted regions. The single-droplet configuration is shown to provide overall higher cooling effect, whereas the multi-droplet has longer and more effective cooling on the area of mutual interaction between droplets.
Attenzione! Scheda prodotto non ancora validata dall'Ateneo
|Data di pubblicazione:||2014|
|Titolo:||Spray cooling by gently-deposited droplets: Experiments and modeling of heat-transfer mechanisms|
|Autori:||Santangelo, Paolo E.; Corticelli, Mauro A.; Tartarini, Paolo|
|Data del convegno:||2014|
|Nome del convegno:||15th International Heat Transfer Conference, IHTC 2014|
|Luogo del convegno:||jpn|
|Titolo del libro:||Proceedings of the 15th International Heat Transfer Conference, IHTC 2014|
|Appare nelle tipologie:||Relazione in Atti di Convegno|
File in questo prodotto:
I documenti presenti in Iris Unimore sono rilasciati con licenza Creative Commons Attribuzione - Non commerciale - Non opere derivate 3.0 Italia, salvo diversa indicazione.
In caso di violazione di copyright, contattare Supporto Iris