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This paper reports results of the computation of the drag force exerted on an oscillating object in quantum turbulence in superfluid $^4$He. The drag force is calculated on the basis of numerical simulations of quantum turbulent flow about the object. The drag force is proportional to the square of the magnitude of the oscillation velocity, which is similar to that in classical turbulence at high Reynolds number. The drag coefficient is also calculated, and its value is found to be of the same order as that observed in previous experiments. The correspondence between quantum and classical turbulences is further clarified by examining the turbulence created by oscillating objects.
We report on the observation of vortex formation in a Bose-Einstein condensate of Rb-87 atoms. Vortices are generated by superimposing an oscillating excitation to the trapping potential introduced by an external magnetic field. For small amplitudes
We study numerically nonuniform quantum turbulence of coflow in a square channel by the vortex filament model. Coflow means that superfluid velocity $bm{v}_s$ and normal fluid velocity $bm{v}_n$ flow in the same direction. Quantum turbulence for ther
A unique method of driving Alfvenic turbulence via an oscillating Langevin antenna is presented. This method of driving is motivated by a desire to inject energy into a finite domain numerical simulation in a manner that models the nonlinear transfer
We discuss the force and torque acting on spherical particles in an ensemble in the presence of a uniform AC electric field. We show that for a torque causing particle rotation to appear the particle must be absorptive. Our proof includes all electro
We investigate numerically simulated collisions between experimentally realistic Bose-Einstein condensate wavepackets, within a regime where highly populated scattering haloes are formed. The theoretical basis for this work is the truncated Wigner me