Characterization of a Griffith-type transonic, laminar-flow airfoil

Armando R. Collazo Garcia, Phillip J Ansell

Research output: Contribution to journalArticle

Abstract

An experimental test campaign was conducted on a transonic Griffith-type airfoil to evaluate the effectiveness of its laminar flow qualities and boundary-layer flow control characteristics in the transonic regime. From the pressure distributions it was observed that the flow control application had a beneficial influence, allowing for a more aggressive pressure recovery downstream of the suction slot and higher recovery pressure values at the trailing edge. At M 0.7 and α 0°, a net profile drag reduction of 10.70% and an increase in the L∕D ratio of 14.68% was observed. PIV experiments were performed to characterize the wake velocity deficit produced by the airfoil, which showed good agreement with the drag performance across every Mach number condition. Surface-oil flow visualization experiments were also performed at the design Mach number of 0.7 to find that the airfoil experienced extensive laminar flow runs regardless of suction application, which were followed by a shock-induced laminar separation bubble before the slot location. In addition, Schlieren imaging experiments were performed at M 0.7 to characterize the unsteady shock behavior. A characteristic shock oscillation frequency of 22.38 Hz was identified and observed to significantly stabilize with the application of suction.

Original languageEnglish (US)
Pages (from-to)1597-1609
Number of pages13
JournalJournal of Aircraft
Volume56
Issue number4
DOIs
StatePublished - Jan 1 2019

Fingerprint

Laminar flow
Airfoils
Flow control
Mach number
Recovery
Drag reduction
Boundary layer flow
Experiments
Flow visualization
Pressure distribution
Drag
Imaging techniques

ASJC Scopus subject areas

  • Aerospace Engineering

Cite this

Characterization of a Griffith-type transonic, laminar-flow airfoil. / Collazo Garcia, Armando R.; Ansell, Phillip J.

In: Journal of Aircraft, Vol. 56, No. 4, 01.01.2019, p. 1597-1609.

Research output: Contribution to journalArticle

Collazo Garcia, Armando R. ; Ansell, Phillip J. / Characterization of a Griffith-type transonic, laminar-flow airfoil. In: Journal of Aircraft. 2019 ; Vol. 56, No. 4. pp. 1597-1609.
@article{8c8458268d5846b2bbf63d8795472901,
title = "Characterization of a Griffith-type transonic, laminar-flow airfoil",
abstract = "An experimental test campaign was conducted on a transonic Griffith-type airfoil to evaluate the effectiveness of its laminar flow qualities and boundary-layer flow control characteristics in the transonic regime. From the pressure distributions it was observed that the flow control application had a beneficial influence, allowing for a more aggressive pressure recovery downstream of the suction slot and higher recovery pressure values at the trailing edge. At M 0.7 and α 0°, a net profile drag reduction of 10.70{\%} and an increase in the L∕D ratio of 14.68{\%} was observed. PIV experiments were performed to characterize the wake velocity deficit produced by the airfoil, which showed good agreement with the drag performance across every Mach number condition. Surface-oil flow visualization experiments were also performed at the design Mach number of 0.7 to find that the airfoil experienced extensive laminar flow runs regardless of suction application, which were followed by a shock-induced laminar separation bubble before the slot location. In addition, Schlieren imaging experiments were performed at M 0.7 to characterize the unsteady shock behavior. A characteristic shock oscillation frequency of 22.38 Hz was identified and observed to significantly stabilize with the application of suction.",
author = "{Collazo Garcia}, {Armando R.} and Ansell, {Phillip J}",
year = "2019",
month = "1",
day = "1",
doi = "10.2514/1.C035221",
language = "English (US)",
volume = "56",
pages = "1597--1609",
journal = "Journal of Aircraft",
issn = "0021-8669",
publisher = "American Institute of Aeronautics and Astronautics Inc. (AIAA)",
number = "4",

}

TY - JOUR

T1 - Characterization of a Griffith-type transonic, laminar-flow airfoil

AU - Collazo Garcia, Armando R.

AU - Ansell, Phillip J

PY - 2019/1/1

Y1 - 2019/1/1

N2 - An experimental test campaign was conducted on a transonic Griffith-type airfoil to evaluate the effectiveness of its laminar flow qualities and boundary-layer flow control characteristics in the transonic regime. From the pressure distributions it was observed that the flow control application had a beneficial influence, allowing for a more aggressive pressure recovery downstream of the suction slot and higher recovery pressure values at the trailing edge. At M 0.7 and α 0°, a net profile drag reduction of 10.70% and an increase in the L∕D ratio of 14.68% was observed. PIV experiments were performed to characterize the wake velocity deficit produced by the airfoil, which showed good agreement with the drag performance across every Mach number condition. Surface-oil flow visualization experiments were also performed at the design Mach number of 0.7 to find that the airfoil experienced extensive laminar flow runs regardless of suction application, which were followed by a shock-induced laminar separation bubble before the slot location. In addition, Schlieren imaging experiments were performed at M 0.7 to characterize the unsteady shock behavior. A characteristic shock oscillation frequency of 22.38 Hz was identified and observed to significantly stabilize with the application of suction.

AB - An experimental test campaign was conducted on a transonic Griffith-type airfoil to evaluate the effectiveness of its laminar flow qualities and boundary-layer flow control characteristics in the transonic regime. From the pressure distributions it was observed that the flow control application had a beneficial influence, allowing for a more aggressive pressure recovery downstream of the suction slot and higher recovery pressure values at the trailing edge. At M 0.7 and α 0°, a net profile drag reduction of 10.70% and an increase in the L∕D ratio of 14.68% was observed. PIV experiments were performed to characterize the wake velocity deficit produced by the airfoil, which showed good agreement with the drag performance across every Mach number condition. Surface-oil flow visualization experiments were also performed at the design Mach number of 0.7 to find that the airfoil experienced extensive laminar flow runs regardless of suction application, which were followed by a shock-induced laminar separation bubble before the slot location. In addition, Schlieren imaging experiments were performed at M 0.7 to characterize the unsteady shock behavior. A characteristic shock oscillation frequency of 22.38 Hz was identified and observed to significantly stabilize with the application of suction.

UR - http://www.scopus.com/inward/record.url?scp=85071237472&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85071237472&partnerID=8YFLogxK

U2 - 10.2514/1.C035221

DO - 10.2514/1.C035221

M3 - Article

AN - SCOPUS:85071237472

VL - 56

SP - 1597

EP - 1609

JO - Journal of Aircraft

JF - Journal of Aircraft

SN - 0021-8669

IS - 4

ER -