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Indexed by:期刊论文

Date of Publication:2019-05-01

Journal:INTERNATIONAL JOURNAL OF REFRIGERATION-REVUE INTERNATIONALE DU FROID

Included Journals:SCIE、EI

Volume:101

Page Number:106-116

ISSN No.:0140-7007

Key Words:Ranque-Hilsch vortex tube; LDV; Flow structure; Energy separation; Reverse flow boundary; Performance

Abstract:In this study, transparent vortex tubes of diameter 30 mm were designed for the main tube visualisation and a 2D laser Doppler velocimetry (LDV) measurement was adopted to investigate the mean flow field on the meridian plane. The distributions of the axial and radial velocities, and particularly the reverse flow boundary, were obtained for understanding the characteristics of large-scale vortex structures. Various operation conditions with different cold mass fractions (0.1-0.9), tube lengths (360 mm, 600 mm, and 900 mm), and inlet pressures (0.1 bar and 0.2 bar) were studied to reveal how the reverse flow boundary affects the energy separation performance. The LDV results show that the mean axial velocity distribution present good axial symmetry, and increasing the cold mass fraction results in an expansion of the reverse flow boundary as reported for previous numerical calculations. A deterioration in the energy separation performance due to an excessively short or long tube was revealed, and the proposed tube optimization criteria were proven. (C) 2019 Elsevier Ltd and IIR. All rights reserved.