Eventos Anais de eventos
ENCIT 2016
16th Brazilian Congress of Thermal Sciences and Engineering
EXPERIMENTAL EVALUATION OF CONVECTION HEAT TRANSFER ON CYLINDERS AND NOT CYLINDRICAL GEOMETRIES
Submission Author:
Cristiano meneghini , SC
Co-Authors:
Daniela Pintro, Antonio Carlos Ferreira
Presenter: Cristiano meneghini
doi://10.26678/ABCM.ENCIT2016.CIT2016-0259
Abstract
In the present scenario the most varied forms of heat transfer are studied for optimization of industrial processes involved. Such optimization is present in times where the thermal energy is extremely crucial, where the increase of the processes involving heat transfer efficiency should be prioritized. Among one of the topics involving thermal energy has the local heat transfer coefficient h by convection, which determines the intensity of heat transfer by the phenomenon between a surface and a fluid flow. The objective of this study is the evaluation of the local heat transfer coefficient in cylindrical and not cylindrical geometries. This assembly constitutes an experimental bench using forced convection, which through empirical correlations is possible to determine the value of the local heat transfer coefficient. The determination of the coefficient h, using the empirical correlations given by Hilpert (1933), Zukauskas (1972) and Churcill e Bernstein (1977). The experiments were conducted in Thermal Sciences Laboratory at the University of the West of Santa Catarina, where was used a bench equipped with temperature gauges and air velocity. For the forced convection could be controlled, was used an axial fan with a frequency inverter, which allowed obtaining different range of Reynolds numbers. It was observed that for different Reynolds number, the values of local heat transfer convection coefficient of the authors cited can be considered satisfactory for the geometries studied. Subsequently they were performed simulations using commercial software in order to perform a comparison of results obtained experimentally. The experimental and simulation results show us that the local heat transfer h it is in agreement with the expected values, and both grow linearly to not cylindrical geometries. Based on the results obtained, it can be said that the experimental bench is validated and can be applied in the development of other studies.
Keywords
convection heat transfer., forced convection
