Some flow properties of liquid helium II
Swim, Richard Taylor
Doctor of Philosophy
The properties of pressure-induced flow of liquid helium II have been studied by the observation of the temperature and pressure dependence of the flow in narrow channels. The channels are in the form of an annular slit between two flat glass plates. Measurements of the flow rates have been made with hydrostatic pressures up to 2.3 x 103 dynes/cm 2, at temperatures between 1.39 and 2.10°K, and with slit widths of 2.4 and 4.3 microns. The observed flow rates have the same temperature dependence as the superfluid concentration in helium II. At lower pressure heads the flow rate is proportional to a power of the pressure head. The power is nearly independent of temperature but decreases with decreasing slit width. At higher pressures the flow rates reach saturation values at which they are independent of pressure. These saturation rates also have the temperature dependence of the superfluid concentration. The modifications necessary in the existing theories to explain these results are considered in a qualitative manner, and the need for further experiments of this nature is pointed out.
Condensed matter physics