An Experiment on Frosting Phenomena in a Fin Bundle
نویسندگان
چکیده
This paper deals with an experimental study on the frosting phenomena using a fin bundle, which is an expanded model for the fins of the heat exchanger. The overall characteristics such as total frost mass, mass flux, pressure drop, sensible and latent heat fluxes and the local characteristics such as local temperature, local heat flux and local frost thickness were investigated under several experimental conditions composed of cooling block temperature, humidity and velocity of air. It was found that the cooling block temperature and air humidity affect considerably the total frost mass. The mass flux in all of conditions decreased gradually with time, while the pressure drop increased with frost deposition. The sensible heat flux was nearly constant due to the same airflow rate, but the latent heat flux decreased gradually with time. The local heat and mass transfer characteristics were also clarified by developing an approximation equation for the fin temperature and considering the energy and mass balances to the control volume.
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