Fire Safety Science Digital Archive

Data originally obtained in the calibration of a 1 in. diameter disk radiometer have been used to evaluate the natural convection heat transfer coefficient for a vertical disk. It is suggested that the correlation between the Nusselt number and the Grashof number for large rectangular vertical plates can be applied to disks if it is modified to allow for the variation in height across the disk and for the limiting value of the Nusselt number at zero Grashof number. It is found that the predicted results are generally in agreement with those found experimentally.