Eventos Anais de eventos
COBEM 2019
25th International Congress of Mechanical Engineering
EXPERIMENTAL DETERMINATION OF SURFACE EMISSIVITY USING THE COOLING PROCESS OF A SOLID IN AMBIENT AIR
Submission Author:
Luis Martins , RS
Co-Authors:
Luis Martins, Renato Letizia Garcia, Edson Chiaramonte, Gunther Barbosa, João Marcos Guido do Carmo
Presenter: Luis Martins
doi://10.26678/ABCM.COBEM2019.COB2019-1601
Abstract
This work describes a quantitative experiment that evaluate the surface emissivity of a heated steel cylinder subjected to a cooling process to the surrounding air. The employed methodology highlights the importance of adopting a thermal balance that includes the mechanisms of convection and radiation heat transfer in the solid interface. Tests were carried out with identical objects painted in different colors in order to demonstrate that the radiation heat rate is determined by the characteristics of the radiant surface. In this experiment, the students are asked to prepare an electronic spreadsheet in order to perform calculations and analyze the consistency of the experimental results obtained.
Keywords
convection and radiation, cooling of a solid, simple low cost experiments, unsteady heat transfer, emissivity
