Loading...

Power spectrum and FFT-based signal analysis in turbulence measurements

Dehghan Manshadi, M ; Sharif University of Technology | 2009

812 Viewed
  1. Type of Document: Article
  2. Publisher: 2009
  3. Abstract:
  4. In this research, the employment of an innovative but simple and cost effective method for turbulent reduction in a low speed wind tunnel is investigated and the effect of this turbulence reduction on the Power Spectrum and FFT-Based signals that obtained from Hot-wire Anemometry is studied. These terms represents the amount of power contained in the signals. Several situations are studied in this paper. One of these situations is when there are four screens in the settling chamber of the wind tunnel and after that by adding the trip strip in the contraction region of the wind tunnel the tests were repeated. In the next stage, three screens were removed from the settling chamber of the wind tunnel and the retests were done. Results showed that by adding the trip strip in the contraction of wind tunnel and with adding the screens, the amount of power decreased dramatically in compare with the situation with one screen in the settling chamber. This reduction in the amount of power showed that the fluctuations of longitudinal component of velocity, i.e. turbulence intensity decreased significantly. In the other word, the energy in the fluid with high turbulence level is more than the condition with the low turbulence one
  5. Keywords:
  6. Wind tunnel ; Cost-effective methods ; FFT ; Hot-wire anemometry ; Longitudinal components ; Low-speed wind tunnel ; Settling chambers ; Trip strips ; Turbulence intensity ; Turbulence level ; Turbulence measurements ; Turbulence reduction ; Aerodynamics ; Fast Fourier transforms ; Power spectrum ; Shrinkage ; Signal analysis ; Tunnels ; Turbulence ; Wind tunnels
  7. Source: World Academy of Science, Engineering and Technology ; Volume 40 , 2009 , Pages 275-278 ; 2010376X (ISSN)
  8. URL: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.193.831&rep=rep1&type=pdf