Flow visualization in a Ranque-Hilsch vortex tube / Yusman Istihat … [et al.]

This paper presents the results of flow visualization in a Ranque-Hilsch vortex tube (RHVT). The RHVT has been newly designed and locally fabricated. Dimensional analysis and similarity was carried out by taking comparison between real model (Blue Model) of RHVT and prototype (Clear Prototype) using acrylic. The research objective is to visualize flow patterns inside the tube and water is chosen as the flowing fluid. Several methods of visualization were adapted in this exercise especially for observing the particles movement throughout the process. Still pictures and videos were recorded and formation of vortex was studied. It is observed that the flow pattern of circulation was presented and visible. The existence of two swirling flows can be seen and documented. The frames of pictures show a flow pattern of forward and backward flows obtained from the vortex tube

The Effect of Orifice Diameter to the Acoustic Signals Captured at the Cold Part of a Ranque-Hilsch Vortex Tube

In this study, acoustic analysis and thermofluid performance of a Ranque-Hilsch Vortex Tube (RHVT) is experimentally investigated under different orifice diameters at its cold tube. The orifice diameters used are 2mm, 3 mm, 4 mm, 5 mm and 6 mm. The inlet pressure (gage) is set at 10 psi, 15 psi, 20 psi and 25 psi for each orifice diameter. The sound produced by the tube is recorded using a microphone located outside the cold tube. The acoustic signal is processed using Fast-Fourier Transform (FFT) to obtain the frequency representation. Main frequencies are then extracted to constitute the signature of the signal for that specific configuration. It is observed that different orifice diameters give different signatures. These signatures are then associated with the thermofluid performance of the device to obtain the relation among the parameters