A study of thermal counterflow using particle tracking velocimetry

作者：Chagovets T V^*; Van Sciver S W

来源：Physics of Fluids, 2011, 23(10): 107102.

DOI：10.1063/1.3657084

The motion of solid hydrogen particles in He II thermal counterflow has been measured using the particle tracking velocimetry technique. The tracers can move with the velocity comparable to the velocity of the normal fluid. However, below some transition velocity, the particles can be trapped on individual vortex lines and towed by the vortex tangle in the direction of superfluid flow. Above this transition velocity, the Stokes drag with the normal fluid dislodges the trapped particles from vortex cores and such particles move in the same direction as the normal fluid, albeit with lower average velocity. We discuss the measurement of the transition velocity and the mechanism by which tracers may be trapped by or dislodged from quantized vortices.

• 出版日期2011-10