Eventos Anais de eventos
ENCIT 2018
Brazilian Congress of Thermal Sciences and Engineering
EXPERIMENTAL STUDY OF BOILING PHENOMENON IN THE EVAPORATOR OF A GLASS THERMOSYPHON
Submission Author:
PAULO HENRIQUE DIAS DOS SANTOS , PR
Co-Authors:
Diógenes Oliveira de Souza, Ramaiana M. Davies, Cesar Barddal, PAULO HENRIQUE DIAS DOS SANTOS, Eduardo Nunes dos Santos, Marco Jose Da Silva, Thiago Antonini Alves, Sarah Nunes Argentin
Presenter: Diógenes Oliveira de Souza
doi://10.26678/ABCM.ENCIT2018.CIT18-0668
Abstract
Solar collectors assisted by thermosyphons has become an alternative for water heating for home environments due to its clean source of energy. However, for the correct development of the thermosyphons specific correlations are necessary for the boiling and condensation processes which occur within them. There are several studies regarding on correlations for the boiling process in thermosyphons and each one has a different focus: some correlations analyze the pool boiling process, others one film boiling and there are still those that analyze both processes by varying the filling charge ratio. In this work, the pool and film boiling processes and the transition between each boiling regimes are experimentally analyzed for a thermosyphon with filling charge ratio of 100% (in relation to the evaporator volume). An experimental set up was constructed with a glass thermosyphon for testing using water. It was used advanced technology of measurement regarding on two-phase flow and for that two wire-mesh sensors were installed to measure flow hydrodynamic parameters (void fraction, bubble velocity, piston length, frequency of bubbles passage). The data obtained will be used to estimate the boiling heat transfer coefficient through correlations used in literature for heat loads (50 and 70 W) applied to the evaporator for both regimes (pool and film boiling).
Keywords
Thermosyphons, evaporator, Boiling regimes, wire-mesh sensor
