Imperial College London
Portrait Picture

ProfessorMatthewSanter

Faculty of Engineering, Department of Aeronautics

Professor of Aerospace Structures
 
 
 
//

Contact

 

+44 (0)20 7594 5117m.santer

 
 
//

Location

 

335City and Guilds BuildingSouth Kensington Campus

//

Summary

 

Publications

Citation

BibTex format

@article{Bird:2018:10.1007/s10494-018-9926-2,
author = {Bird, J and Santer, M and Morrison, J},
doi = {10.1007/s10494-018-9926-2},
journal = {Flow, Turbulence and Combustion},
pages = {1015--1035},
title = {Experimental control of turbulent boundary layers with in-plane travelling waves},
url = {http://dx.doi.org/10.1007/s10494-018-9926-2},
volume = {100},
year = {2018}
}
Download

RIS format (EndNote, RefMan)

TY  - JOUR
AB  - The experimental control of turbulent boundary layers using stream-wise travelling waves of spanwise wall velocity, produced using a novel activesurface,  is  outlined  in  this  paper.  The  innovative  surface  comprises  a  pneu-matically actuated compliant structure based on the kagome lattice geometry,supporting  a  pre-tensioned  membrane  skin.  Careful  design  of  the  structureenables waves of variable length and speed to be produced in the flat surfacein a robust and repeatable way, at frequencies and amplitudes known to havea favourable influence on the boundary layer. Two surfaces were developed,a  preliminary  module  extending  152 mm  in  the  streamwise  direction,  and  alonger one with a fetch of 2.9 m so that the boundary layer can adjust to thenew surface condition imposed by the forcing. With a shorter, 1.5 m portionof  the  surface  actuated,  generating  an  upstream-travelling  wave,  a  drag  re-duction  of  21.5%  was  recorded  in  the  boundary  layer  withReτ=  1125.  Atthe same flow conditions, a downstream-travelling produced a much smallerdrag reduction of 2.6%, agreeing with the observed trends in current simula-tions. The drag reduction was determined with constant temperature hot-wiremeasurements of the mean velocity gradient in the viscous sublayer, while si-multaneous laser Doppler vibrometer measurements of the surface recorded thewall motion. Despite the mechanics of the dynamic surface resulting in someout-of-plane motion (which is small in comparison to the in-plane streamwisemovement), the positive drag reduction results are encouraging for future in-vestigations at higher Reynolds numbers.
AU  - Bird,J
AU  - Santer,M
AU  - Morrison,J
DO  - 10.1007/s10494-018-9926-2
EP  - 1035
PY  - 2018///
SN  - 1386-6184
SP  - 1015
TI  - Experimental control of turbulent boundary layers with in-plane travelling waves
T2  - Flow, Turbulence and Combustion
UR  - http://dx.doi.org/10.1007/s10494-018-9926-2
UR  - http://hdl.handle.net/10044/1/58960
VL  - 100
ER  -
Download