Abstract
The heat transfer of superfluid helium (He II) in a rectangular channel has been investigated both experimentally and numerically. The channel end is kept open to a He II bath under an atmospheric pressure condition. A one-dimensional heat transfer model, which can predict the temperature rise at the end of the He II channel and λ-transition heat flux, is proposed in the present study. This model is developed on the basis of heat conduction by taking into account heat transfer not only in the channel but also in the He II bath. The supply of heat to the channel results in a temperature rise at the channel end. Larger temperature rise at the channel end leads to a smaller value of λ-transition heat flux in the channel. In the case of λ-transition heat flux being supplied to the channel, an increase in aspect ratio, which is defined as the ratio of the gap to the length of the channel, results in an increase in the value of temperature rise at the channel end. A satisfactory agreement between the measured data and the results of calculation on the basis of the present model is observed for the range of aspect ratio tested in this study.
