Since there is no reliable surface-area formula available for the calculation of the heat-transfer characteristics
of an insulated oblate spheroid, in this investigation, highly accurate oblate spheroid surface area is
obtained by a simple numerical integration method. Based on the accurate oblate spheroid surface area, a
reliable one-dimensional approximate solution of an insulated oblate spheroid container can be obtained
with a one-dimensional RPSWT model. By comparing with accurate three-dimensional numerical results,
it is found that in cases of low external convective coefficient (ho = 8.3Wm2 K1), long–short-axes ratio
a=b53, and insulation thickness t=R252, errors are within 3%. In rarer situations with a=b55 and t=R252,
the errors are within 5.5%. The above results are almost independent with the internal flow convective
coefficient (hi from 30 to 105Wm2 K1) and dimensionless container size (0.5R2ho/Ks from 1.55 to 155).
Relation:
Energy Conversion and Management 50 (2009) 1871–1878