| Texto completo | |
| Autor(es): |
Amaral, F. R.
[1]
;
Serrano Rico, J. C.
[2]
;
Bresci, C. S.
[3]
;
Beraldo, M. M.
[3]
;
Victorino, V. B.
[3]
;
Gennaro, E. M.
[4]
;
Medeiros, M. A. F.
[3]
Número total de Autores: 7
|
| Afiliação do(s) autor(es): | [1] Aeronaut Inst Technol ITA, Dept Aerodynam, Sao Jose Dos Campos - Brazil
[2] Univ Pamplona, Dept Mech Engn, Pamplona - Colombia
[3] Univ Sao Paulo, Dept Aeronaut Engn, Sao Carlos - Brazil
[4] Sao Paulo State Univ UNESP, Sao Joao Da Boa Vista - Brazil
Número total de Afiliações: 4
|
| Tipo de documento: | Artigo Científico |
| Fonte: | AERONAUTICAL JOURNAL; OCT 2021. |
| Citações Web of Science: | 0 |
| Resumo | |
This paper introduces the Low Acoustic Noise and Turbulence (LANT) wind tunnel of the Sao Carlos School of Engineering, University of Sao Paulo (USP-EESC), Brazil. The closed-loop wind tunnel features several devices to improve flow uniformity, reduce swirl, and lower the background acoustic noise and turbulence, enabling stability and aeroacoustic experiments. The design criteria was based on the best practices reported, in particular for low turbulence wind tunnels. Yet, these criteria are conflicting and we discuss the decisions that had to be made and present flow quality results that were achieved. The 16-bladed axial fan with 13-blade stators is driven by a variable-speed electric motor. At the corners, 100 mm dense acoustic foam is installed on the vertical walls, floor and ceiling, and the turning vanes are filled with acoustic-absorbing material. The long settling chamber contains a 3.175 mm mesh hexagonal honeycomb and five fine mesh nylon screens, ending in a 7:1 area ratio short contraction. The 3-m long closed-working section has a 1x1 m(2) cross-section area. At 15 m/s the working section wall boundary layer is less than 100 mm thick, providing an area of at least 800x800 mm(2) where the streamwise flow uniformity was within 1%. In the 10-30 m/s flow speed range, the turbulence intensity ranged from 0.05% to 0.071% and the background acoustic noise level, obtained with an inflow microphone, ranged from 90 and 110 dB. A benchmark experiment on a flat plate boundary layer produced an almost perfect two-dimensional Blasius profile up to Re-x approximate to 2.5x10(6). A beamforming benchmark experiment on aeroacoustics accurately identified the sound emitted by a cylinder immersed in the flow. (AU) | |
| Processo FAPESP: | 19/15366-7 - Estudo experimental do efeito de uma cavidade sobre a transição da camada limite |
| Beneficiário: | Marcello Augusto Faraco de Medeiros |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |
| Processo FAPESP: | 06/52568-7 - Aeronave silenciosa: uma investigação em aeronáutica |
| Beneficiário: | Julio Romano Meneghini |
| Modalidade de apoio: | Auxílio à Pesquisa - Parceria para Inovação Tecnológica - PITE |