Vorticity scattering measurements in a superfluid inertial round jet
نویسنده
چکیده
The aim of this proceeding paper is twofold. First, we present a newly developed cryogenic testing facility where a steady high Reynolds liquid helium inertial round jet flow is generated allowing to address classical turbulence issues, such as statistical intermittency, and quantum turbulence when the facility is operating in superfluid helium. Secondly we present the first spatial Fourier vorticity modes measurements made both above and below the superfluid transition at different nozzle velocities. These preliminary results were obtained by probing the vorticity flow-field with the ultrasonic scattering technique.
منابع مشابه
Turbulent structure during transition to self-similarity in a round jet
The developing turbulent region of a round jet was investigated using an improved implementation of digital particle image velocimetry (DPIV). The two-dimensional flow field in planes normal and parallel to the axial velocity was measured at locations between 15 and 30 diameters downstream, for two Reynolds numbers of 5500 and 16,000. The study consisted of instantaneous snapshots of the veloci...
متن کاملThe turbulent matter field of ultracold atoms
Nowadays, the term turbulence is being used in a much broader context than its original classical hydrodynamic meaning of cascading vorticity. Classically, turbulence arises as fluid motion spawns swirls that break into smaller and smaller swirls, leading to vortices at all length scales. In superfluids, however, quantization of velocity circulation in the superfluid component coupled to a cont...
متن کاملScattering of second sound waves by quantum vorticity.
A new method of detection and measurement of quantum vorticity by scattering second sound off quantized vortices in superfluid Helium is suggested. Theoretical calculations of the relative amplitude of the scattered second sound waves from a single quantum vortex, a vortex ring, and bulk vorticity are presented. The relevant estimates show that an experimental verification of the method is feas...
متن کاملImpact of density differences on turbulent round jets
Jets with different density than the fluid into which they are issued, constitute an important class of flows relevant for applications in technical and environmental situations. In this work three cases of variable-density turbulent round jets discharging from a straight circular pipe into a weakly confined low-speed co-flowing air stream are studied with the aid of large eddy simulation. The ...
متن کاملTyphoon-induced, highly nonlinear internal solitary waves off the east coast of Korea
[1] Highly nonlinear internal solitary waves (ISWs) propagating both onshore and offshore were detected in a SAR image taken approximately 19 hours after typhoon MAEMI’s passage across the east coast of Korea. Analysis of ocean buoy data suggests that the ISWs were generated by near-inertial waves in response to typhoon wind. The near-inertial waves can propagate seaward due to a downwelling co...
متن کامل