ARDB E 1 250 Closure

8/13/2019 ARDB E 1 250 Closure

1/21

EAD, National Aerospace Laborotories, Bangalore

S.B.Verma

CSIR-NAL

AR&DB Annual Symposium, 13-14 May 2011

Shock Wave Boundary-Layer Interaction Study on a 20o

Compression Corner Using PSP and Kulites

Principal Investigator

S.B.Verma

Co-investigatorChanna Raju and Manisankar, C.

Council of Scientific and Industrial Research (CSIR),

Experimental Aerodynamics Division, National Aerospace Laboratories

Bangalore 560 017

AR&DB Sanction Ref : AR&DB Project DARO/08/1031316/M/IAR& DB Project No. : 1316

Date of Commencement : July 29th, 2009

Original PDC : June, 2011

Project Cost : Rs.8.999 Lakhs


2/21


S.B.Verma

CSIR-NAL


Introduction

ramp flows

forebody ramp flows

axial corner

(glancing shock)shock reflection

crossing-shock

interaction

Typical Vehicle Components where SWBLI is Expected

Wind tunnel experiments are indispensable, especially

to investigate pressure loads, shock unsteadiness characteristics in regions

of interest and to look for the mechanisms responsible

to obtain the desired design information with sufficient reliability

neck region

interaction point (I)

separation

compression fan

sonic line

undisturbed

boundary-layer

Xphysep

LsepL

reattachment

compression fan

separated

shear layer


3/21


S.B.Verma

CSIR-NAL


Specific Objectives of the Proposal

To gain a broad understanding of the shock-wave boundary layer interaction

(SWBLI) phenomena on a 20ocompression corner with emphasis on shock

unsteadiness and the related surface-flow structure development at freestream

Mach number of 2.0.

To compare the SWBLI characteristics on the ramp by varying the boundary-

layer thickness () and using one vortex-generator configuration

To obtain surface pressure map of such interactions using PSP to get better

insight of the global mean-flow characteristics

Surface oil visualization to study surface flow characteristics and Spark Schlieren

visualization for the different test cases.


4/21


S.B.Verma

CSIR-NAL


Actual Model Mounted in the 0.3m Tunnel

For Pressure measurements and schlieren Moundel mounting for PSP


5/21


6/21


S.B.Verma

CSIR-NAL


boundary-layer tripramp

flat plate

leading edge plate

strut

sting support

model support strut

schlieren window

base plate

Compression Corner Model


7/21EAD, National Aerospace Laborotories, Bangalore

S.B.Verma

CSIR-NAL


10 Kulite transducer

Locations (XT-140M)

10m

m5m

m

5m

m

VG

strip

5m

m

Kulite XCQ-93 6nos.

(a) VG1

(a) VG2

Mechanical Vortex Generators

3

10o

3.5

3.5

10o

4

X

Z

Y



S.B.Verma

CSIR-NAL


separation shock

reattachment shock

trip initiated shocks

tripped blayer

reattached

blayer

With trip; no VG

separation shock

reattachment shock


shocks from VGs

reattached

blayer

With trip; VG1

separation shock

reattachment shock


shocks from VGs

reattached

blayer

With trip; VG2

With trip; noVG

With trip; VG1

With trip; VG2

Spark Schlieren Pictures

=1.6mm; 27.5 =3.85mm; 12.5



S.B.Verma

CSIR-NAL


Spark Schlieren Movies

no VG VG1



S.B.Verma

CSIR-NAL


(a) no VG

separation line

reattachment line

(b) VG1

corrugated

separation linevortex trails

reattachment line

(c) VG2

corrugated

separation line

vortex trails

striation patternreattachment line

Surface Oil Visualization: h/= 0.65



S.B.Verma

CSIR-NAL


vortex trails

corrugated

separation line

vortex trails

corrugated

separation line

Surface Oil Visualization: h/= 0.26

VG1 VG2



S.B.Verma

CSIR-NAL


Schematic of the Surface Flow Development

Overall surface flow pattern

X

Z

Y

corrugated shock

micro-ramps

streamwise

CRVs

main flow

reverse flow

flow

reverse flowcorrugated

separation line

Corrugated separation line pattern



S.B.Verma

CSIR-NAL


Streamwise Mean Pressure and rmsDistribution

X/L

Pw

/P

0.7 0.8 0.9 1 1.1 1.20

1

2

3

4

no VG

VG1

VG2

(a)

(d)

X/L

w

/P

w

0.6 0.7 0.8 0.9 1 1.1 1.20

0.02

0.04

0.06

0.08

0.1

no VG

VG1

VG2

(d)

base plate ramp section

corner location

(c)

X/L

w

0.6 0.7 0.8 0.9 1 1.1 1.20

1

2

3

4

no VG

VG1

VG2

(c)

base plate ramp section

corner location

h/=0.65 h/=0.26

(b)

X/L

w

/P

w

0.7 0.8 0.9 1 1.1 1.20

0.02

0.04

0.06

0.08

0.1

no VG

VG1

VG2



S.B.Verma

CSIR-NAL


Spectral Analysis

frequency (Hz)

G(f)(p

si2/Hz)

100

101

102

103

104

10510

-10

10-8

10-6

10-4

10-2

100

no VG

VG1

VG2

(a)X/L= 0.951

Separation region (1)

frequency (Hz)

G(f)(psi

2/Hz)

100

101

102

103

104

10510

-10

10-8

10-6

10-4

10

-2

100

no VG

VG1

VG2

(c)X/L= 1.017

reattachment region (3)

frequency (Hz)

G(f)(p

si2/Hz)

100

101

102

103

104

10510

-10

10-8

10-6

10-4

10-2

100

no VG

VG1

VG2

(b)X/L= 0.97

Separated region (2)

frequency (Hz)

G(f)(psi

2/Hz)

100

101

102

103

104

10510

-10

10-8

10-6

10-4

10

-2

100

no VG

VG1

VG2

(d)X/L= 1.089

Downstream of reattachment (4)

1

23 4

X/L

w/P

w

0.7 0.8 0.9 1 1.1 1.20

0.02

0.04

0.06

0.08

0.1

no VG

VG1

VG2


15/21



S.B.Verma

CSIR-NAL


X (mm)

Pw

/P

200 220 240 260 280 300 3200.5

1

1.5

2

2.5

3

transducer - no VG

PSP - no VG

Y (mm)

Cp

-0.2 -0.1 0 0.1 0.20

0.1

0.2

(b)

Y (mm)

Cp

-0.2 -0.1 0 0.1 0.20

0.1

0.2

(c)

X (mm)

Pw

/P

240 250 260 270 2800.5

1

1.5

2

PSP - no VG

PSP - VG1

PSP - VG2

(a)

PSP Measurements



S.B.Verma

CSIR-NAL


time (ms)

Rpp

(0,0,

)

0 0.3 0.6 0.9 1.2 1.50

0.2

0.4

0.6

0.8

1

1.2

0.912

0.931

0.951

0.971

1.017

1.035

(a)

time (ms)

Rpp

(0,0,

)

0 0.3 0.6 0.9 1.2 1.50

0.2

0.4

0.6

0.8

1

1.20.892

0.912

0.931

0.951

0.971

1.017

1.035

(b)

time (ms)

Rpp

(0,0,

)

0 0.3 0.6 0.9 1.2 1.50

0.2

0.4

0.6

0.8

1

1.20.912

0.931

0.951

0.971

1.017

1.035

(c)

Auto correlation Measurements

no VG VG1 VG2


18/21


S.B.Verma

CSIR-NAL


Cross - correlation Measurements

(a)

time (ms)

Rpp

(,0,

)

-2 -1.5 -1 -0.5 0 0.5 1 1.5 2-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

0.6

0.912 0.931

0.912 0.951

0.931 0.951

0.951 0.971

time (ms)

Rpp

(,0,

)

-2 -1.5 -1 -0.5 0 0.5 1 1.5 2-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

0.60.892 0.912

0.912 0.951

0.931 0.9510.951 0.971

(b)

time (ms)

Rpp

(,0,

)

-2 -1.5 -1 -0.5 0 0.5 1 1.5 2-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

0.60.912 0.931

0.912 0.951

0.931 0.951

0.951 0.971

(c)

no VG VG1 VG2


19/21


S.B.Verma

CSIR-NAL


Conclusions

Control devices generate streamwise vortices that dramatically modify the overall

flow structure development in the entire interaction region.

A well-defined separation line (with no control) gets replaced by a highly corrugated

separation line (with control).

A well defined reattachment line gets replaced by a striation pattern (with control)

In the intermittent region of separation, a significant reduction in peak rmsvalue (by

33%) for VG1 followed by VG2 (by 44%) occurs

VG1 configuration shows favorable flow control in both axial locations and hence, seems

to be a better flow control VG configuration

The comparison between the pressure port data and PSP is generally good

The spanwise wall pressure variation shows a sinusoidal pattern indicating trails of

vortices generated from the VG configurations

Flow control helps reduce the fluctuations of the separation shock and hence, alleviate

the fluctuating pressure loads

Suggestions for future work:Effect of micro-ramps need to be studied in both subsonic and supersonic flows

Other flow control devices such as air-jet vortex generators (skew angle) need to be investigated

Application of these devices to other SWBLIs such as swept fin, blunt fin etc. needs to be tested


20/21


S.B.Verma

CSIR-NAL


Statement of Account

Period Costs released (under

different heads)

Expenditure incurred

(under different heads)

upto 30.04.2011

Balance as on

30.04.11 (under

different heads)

(Rs in lakhs) (Rs in lakhs) (Rs in lakhs)

2009-11 Capital Equipment

3.90

3.90 0.00

Research staff2.16

2.16 0.00

TA/DA0.45

0.45 0.00

Consumables1.25

1.25 0.00

Contingencies0.40

0.40 0.00

Overheads

0.839

0.839 0.00

Total 8.999 8.999 0.00


21/21

EAD National Aerospace Laborotories Bangalore

S.B.Verma

CSIR NAL


Date post:	04-Jun-2018
Category:	Documents
Upload:	mani-sankar
View:	214 times
Download:	0 times

ARDB E 1 250 Closure

Documents