Investigation of The Decay of a Single vortex with PIV Technique

Main Author: Abadi, Surjo
Format: Article PeerReviewed Book
Bahasa: eng
Terbitan: Department of Mechanical Engineering, Faculty of Engineering, Universitas Sultan Ageng Tirtayasa , 2020
Subjects:
Online Access: http://repository.uki.ac.id/2853/1/InvestigationofTheDecay.pdf
http://repository.uki.ac.id/2853/2/ReviewerInvestigationofTheDecay.pdf
http://repository.uki.ac.id/2853/
https://jurnal.untirta.ac.id/index.php/jwl/index
Daftar Isi:
  • The formation and development of a single vortex are investigated in a wind tunnel. The wake from a rectangular lifting wing based on a CLARK-Y profile of 11.7% is studied up to 80 chords downstream. Digital particle image velocimetry is used to measure the velocity field in the cross-stream plane from which is the vortex is measured. Two different experimental tests were carried out in two different tunnel conditions, without and with a grid. From the first condition, the vortex is observed to be relatively stable and long–lived. A correlation for the peak tangential velocity uθ, max, and the vortex core rc has been compared with the Lamb-Oseen model, and it gives a fair agreement. The circulation Γ is observed to be proportional to the free-stream U∞ (range 8 − 20 m/s) and the angle of attack α (range 1−12 deg). The vorticity ω, however, diffuses over time within the growth of the vortex core rc. The Squire model can approach this growth. The vortex characteristics become weaker when the experiments are performed under grid turbulence conditions. Due to the influence of the grid turbulence, some experiments give inconsistent results. It is made it difficult to conclude. However, still, some interesting information is found in this case.