MEASURING NUSSELT NUMBER USING A SINGLE-BLOW REGENERATOR FACILITY

摘要

1-D Numerical models of AMRR systems rely on correlations to determine the fluid-to-solid interactions. Nusselt number correlations are of particular interest because the performance of an AMRR system is extremely sensitive to the heat transfer coefficient. However, at the high Prandtl number and low Reynolds number regimes where AMRR systems will operate there are large discrepancies between the accepted correlations, even for relatively common packing configurations such as a packed bed of uniform diameter spheres. In order to address these issues, a single-blow, passive test facility has been constructed. It is possible to infer the Nusselt number associated with the regenerator packing under test by comparing the outlet temperature variation of the fluid with model results. This paper presents initial data from the facility for a packed bed of spheres. The data has been reduced using both a 1-D and a 2-D model. The 2-D model includes the heat capacity of the wall of the test facility and therefore provides more reliable results. The measurements confirm one of the more widely used correlations.