Measurement of Heat Flux and Heat Transfer Coefficient of an Oxy-Hydrogen Flame Used for Thermal Shock Test

Abstract

Heat flux and heat transfer coefficient profiles of an oxy-hydrogen flame used for thermal shock and thermal fatigue tests of ceramic materials were generated experimentally by measuring the heat lost by the flame through the small annular zones of copper block over which the flame was impinged. The copper block in the form of a hollow cylinder with water inlet and outlet facility was fabricated. In order to impinge the flame over a selected area, pyrophylite rings of varying internal diameters (dia.=3–11 mm) were used. A constant flow of water through the copper block was maintained and the temperatures of the inlet and outlet water were measured to calculate the heat flow parameters. The experiments were repeated by replacing the pyrophylite discs from smaller to bigger holes, thereby, measuring heat input over gradually increasing areas. From the experimental data, the heat flux and heat transfer coefficient profiles were generated by employing standard heat loss equations.