Experimental Investigation and Uncertainty Analysis on Combined Heat Losses Characteristics of a Cylindrical Cavity with Only Bottom Wall Heated at Constant Heat Flux

Abstract

An experiment was performed to explore the effects of inclination, aperture ratio, and heat flux on heat losses of a fully or partially open cylindrical cavity, where only the bottom wall (opposite to the aperture) was heated at constant heat flux. Temperature distributions on cavity bottom and side walls are presented. The empirical correlations of free convection and radiation heat losses in terms of Nusselt number are proposed. The credibility of the experiments was checked by detailed uncertainty analysis. It confirmed that the present experimental results are credible and can be used to validate the relevant numerical codes. In addition, the cavity inclination, aperture ratio, and heat flux significantly affect the combined heat losses characteristics, and the influence of these factors, which is intercoupled to some extent, should be considered at the same time.

Wind Effect on Combined Convection and Surface Radiation Heat Losses of a Fully Open Cylindrical Cavity With Insulation

“…Wu et al [1] systematically summarized the state of the research on mechanism of convection heat loss and presented a comprehensive review. It reveals that the research on natural convection heat loss so far has been fully developed [2][3][4][5], and that of considering wind effect is insufficient.…”

Experimental correlation of natural convection losses from a scale-model solar cavity receiver with non-isothermal surface temperature distribution

“…A number of experimental and numerical investigations have been undertaken that use the boundary condition of constant heat flux applied to various combinations of the side and back wall surfaces in cylindrical cavities (Shen et al, 2015;Wu et al, 2013;Wu, S.-Y. et al, 2014;Wu et al, 2015a;Wu et al, 2015b;Xiao et al, 2020;Xiao et al, 2012) and semi-cylindrical cavities (Chakroun, 2004;Chakroun et al, 1997;Chakroun and Quadri, 2002). Results showing non-isothermal temperature profiles along the cavity side wall form one of the important findings from these studies.…”

Experimental investigations on thermal performance characteristics of a solar cavity receiver

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