Heat conduction by liquid helium II in capillary tubes III. mutual friction

摘要: Abstract Measurements are described of the stable supercritical thermal resistance liquid helium II between 1.2°k and 2.0°K in capillary tubes diameter 52.0 microns, 107.6 microns 366 microns. The results presented terms quantized vortex line theory, values L 0, effective length per unit volume, calculated. Graphs 0 1/2 against relative velocity v straight lines at high velocities, corresponding to a cube law mutual friction form F sn = A ρsρn v(v−v 0)2, as expected from theory Vinen. Values independent tube length, increase with temperature same way found by Vinen, but somewhat larger. At low where average spacing becomes comparable channel width, value drops rather abruptly about one-half. In this region, Vinen's can no longer be apply, plot dimensionless variables (DL 1/2) (mvD/...