NASA Technical Reports Server (NTRS) 20090010226: High-Temperature Structural Instrumentation Developments for Hypersonic Airframe Applications

16.2 MB·English

by  NASA Technical Reports Server (NTRS)

s
e
r
u
t
c
u
r
t
S

d
n High-Temperature Structural
a

,
s Instrumentation Developments
l
a
i
r
e for Hypersonic Airframe Applications
t
a
M

,
s
e
t
i
s
o
p
m
o
C
Anthony (Nino) Piazza, Craig Stephens, Larry Hudson
n
o
NASA Dryden Flight Research Center

e
c
n
e
r
e
f
n
o 33rd Annual Conference on Composites, Materials, and Structures
C
Cocoa Beach / Cape Canaveral, Florida
l
a
u 26-29 January 2009
n
n
A

d
r
3
3
Outline
s
e
r
u
t
c
u
r
t
S

d
n
a

,
s
l
a
i
r
e
t Background
a
M

,
s
e
t Objective
i
s
o
p
m
o
C Sensors

n
o

e
c
n Attachment Techniques
e
r
e
f
n
o
Laboratory Evaluation /
C

l
a
u
Characterization
n
n
A

d
r
3 2
3
Background
s Measurements Laboratory
e
r
u
t Provide strain data for validating finite element models and
c
u thermal-structural analyses
r
t
S
• Develop sensor attachment techniques for relevant structural
d
n
materials at the small test specimen level
a

,
s
– Apply methods to large scale hot-structures test articles
l
a
i
r
e • Perform laboratory tests to characterize sensor and generate
t
a corrections to apply to indicated strains
M

,
s
e
it WW Side LW Side
s
o
p
m
o
C

n
o

e
c
n
e
r
e
f
n
o
C

l
a
u
n
n
A C/SiC X-37 Ruddervator tested under

d
NASA’s ARMD Program (M&S)
r
3 3
3
Background
Extreme Environment Structural Sensing (EESS)
s
e Validated measurements enables optimized
r
u structural designs and verified analysis methods
t
c
u
r Lead: ARMD HYP M&S
t
S Industry

d
n
a Hypersonic Structural DoD

,
s Design Optimization and
l
a Analysis Verification Test
i
r
e Opportunities
t
a NASA
M

,
s
e
t
i
s
o Measurement
p
m Validation, Lead
o Application, and • ARMD HYP M&S EESS
C
Integration
n
o

e
c
n
e
r
e
nf Sensors
o
C
Academia Lead: ARMD HYP ExCap
NASA
l
a
• ARMD NRA and SBIR
u
n • ARMD IVHM
n
A Gov’t Labs Industry

d 4
r
3
3
Objective
Measurements Lab Under EESS
s
e
r Structural Measurements of Interest
u EESS Focus
t • Strain
c • Attached sensors (single-point, distributed
u • Temperature sensing, wireless)
r
St • Heat Flux • Non-contact optical techniques
d • Acceleration • Embedded sensors
n • Self-sensing material
a • Deformation

,
s
l
a
i • Develop SOA of structural sensor technology for hypersonic applications
r
e
t
a – Issue
M
, • Identify / evaluate maturity of structural sensor technology for hypersonic applications
s
e
t – Goal
i
s
o
• Provide NASA the framework to focus effort on high-payoff sensing methods
p
m
• Develop SOA to coordinate current and future HYP M&S development efforts (NRA and
o
C
SBIR)

n
o – Method

e
c
• 2007 HYP M&S NRA – University of Massachusetts
n
e
r –Developing a review / assessment on the state of the art in high-temperature structural sensing
e
f technology
n
o
–Develop report (both public and ITAR versions)
C

l • Solicit input from NASA instrumentation experts as required
a
u
n – Work to Date
n
A
• 1-year NRA effort was initiated in January 2008
d
r
3 5
3
Sensors
Dynamic Strain Measurements (Max Op 1850°F)
s
e
r
u
t High-Temp Quarter-Bridge Strain Gage
c
u
r
t
S
+ EX
d Red
n
a R4 Wheatstone Bridge R1
,
s
l + S - S
a Green White
i
r Black
e
R3
t R2
a (Δ R / R) * GF = RTξ
M
, - EX
es Pro’s --1100000000
t PPTTZZ
i
s
o • Sturdy / rugged thermal sprayed installation --1111000000
p
m and spot-welded leadwire stakedown
o --1122000000 RRoottaattiioonn
C • Available high sample rate DAS, usually AC DDiirreeccttiioonn
00
HHeeaatt // CCooooll RRaattee::
n coupled to negate large ξapp 11 °°FF // sseecc --1133000000 11sstt CCyyccllee
o
22nndd CCyyccllee
--33000000
e 33rrdd CCyyccllee
c Con’s
n )) --1144000000
e --66000000 880000 11000000 11220000 11440000 11660000
er • Large magnitude ξapp primarily due to wire ain (ain (
nf TCR, slope rotates cycle-to-cycle trtr--99000000
SS
o
C 11sstt CCyyccllee
• Sensitivity (GF): Function of temperature --1122000000 22nndd CCyyccllee
l
a
33rrdd CCyyccllee
u
n --1155000000
n 00 550000 11000000 11550000
A Apparent Strain = [TCR / GF + (α - α )] * (ΔT) TTeemmpp ((FF))
gage set sub gage
d
r
3 6
3
Sensors
Static Strain Measurements (Max Op 1850°F, Short-Term)
s
e Single-Mode Gold Coated
r
u
t Extrinsic Fabry-Perot Interferometer (EFPI)
c
u
r Commercially Available
t
S

d
n
a
SM gold coated fiber
,
s Silica micro-capillary:
l 125um dia, 6mm core
a OD = 285mm
i 840nm tuned
r ID = 130mm
e L
t
a C
M

,
s
e
t
i
s
o 840nm, 50μW
p
m
Ceramic
o
C Attach

n
o

e
c
n
e
r L
e G
f
n
o
C
al SSttrraaiinn = δLC / LG (initial), where sensitivity = LG
u
n
Apparent Strain (ξapp) = (α - α ) * ΔT
n sub fiber
A

d
r
3 7
3
Sensors
Static Strain Measurements (Possible Max Op 3000°F)
s
e Multi-Mode Sapphire EFPI
r
u
ct Challenges:
u
r
t • Quality fringes at 100um gap
S

d – Achieve highly polished Sapphire fiber and SiC reflector faces
n
a
– Minimize higher order modes at Sapphire / Si splice
,
s
l
a • Fabricate and transfer to substrate w/o degradation to fridges
i
r
e
• Attach w/o effecting fridges
t
a
M
• Install into test fixture w/o breaking (Sapphire fragile with no coating)

,
s
e • Correct for sensor expansion to derive true strain on low expansion
t
si material such as C/C
o
p
m SiC reflector
o
C Micro-capillary tube

n
o

e
c
n Cement
e
r
e
f
n
o
C

l
a
u
n 0.005-in. thick
n Polyimide coated alumina bases
A Si MM 125um fiber

d
r
3 8
3
Sensors
Static Strain Measurements (Possible Max Op 3000°F)
s
e Multi-Mode Sapphire EFPI
r C/SiC ξapp Specimen
u
t
c
u
r
t
S

d
n
a

,
s
l
a
i
r
e
t
a
M

,
s
e
t
i
s
o
p
m
o
C

n
o

e
c
n Work has been performed through a PHII SBIR with
e
r Lambda Instruments, Inc., POC Jonathon Greene
e
f
n
o
C Strain (micro-in/in)

al μξ = Δs / GL
u
where:
n
n s = cavity gap in microns
A
GL = gage length in millimeters
d
r
3 9
3
Sensors
High-Temp Strain Measurements
s
e
r
u
t WeldableSi EFPI strain
c
sensors (1850 F)
u
r
t
S

d
n
a N2doped core for high-temperature FBG’s (1850 F)
, -metallic coating limited to 1400 F
s
l
a
i
r
e
t
a
M

,
s
e
t
i
s
o
p
m
o
C

n
o
NiTiCoated Bragg
e
c Optical Fiber (UCLA)
n Plasma Basecoat Gold Coated
e (0.002”) Not(cfohre da tGtaoclhdm Ceonatt)ing SM 125 Fiber
r
e
f
n
o
C

l
a
u Rokide Attachment Layer G0r.a2t0in” g
n
n
A

d
r
3 10
3