rotorcraft acoustics and dynamics group activities design and testing 3. ... presentation outline....
TRANSCRIPT
-
SPENN TATE1 8 5 5
Center for Acoustics and Vibration
Rotorcraft Acoustics and Dynamics
Group Activities
Edward C. Smith, ProfessorDirector, Penn State Vertical Lift Research Center
CAV Group Leader
Steve Conlon, Res Associate, PSU ARLAssistant Professor, Aerospace Engineering Dept
Assoc. Director, Vertical Lift Research Center
2011 CAV Workshop
-
SPENN TATE1 8 5 5
Interaction with Other PSU Research Centers
Vertical Lift Research Center
of Excellence
National Centerfor Advanced
Drivetrain Technology
ARL
Condition BasedMaintenance Dept.
Centerfor Acoustics
andVibration
Institutefor
ComputationalScience Composites
ManufacturingTechnology
Center
ARL
ARLiMAST
-
SPENN TATE1 8 5 5
Vertical Lift Center Tech Base
31Faculty
60 +GraduateStudents
100 Undergraduate
Students(Freshman Sem, AHS Chapter,Senior Class, Design projects)
40 ContinuingEducationStudents
(Short course)
5Res Assoc
Penn State ARLNRTC CRI
SBIR Programs
apply & transition
-
SPENN TATE1 8 5 5
VLRCOE Research Portfolio: 2011
1. ROTOR AEROMECHANICS & DYNAMICS
2. AIRFOIL DESIGN and TESTING
3. COMPUTATIONAL FLUID DYNAMICS
4. ACOUSTICS
9. FLIGHT CONTROLS and SIMULATION
8. PROPULSION and DRIVE SYSTEMS
5. STRUCTURES, MATERIALS, and MANUFACTURING
7. ICE PROTECTION
6. CONDITION-BASED MAINTENANCE
10. DUCTED FAN AIR VEHICLES11. VARIABLE SPEED (RPM) & COMPOUND ROTORCRAFT
-
SPENN TATE1 8 5 5
Group Highlights (5 min)
Preparation and Submission of 2011-2016 VLRCOE Renewal Proposal
Individual Project Highlights
- Multi-State Damper: Design and Test (5 min)- Ultrasonic Anti-Icing: Recent progress (5 min)
- Airframe Structural Health Monitoring (15 min)(Prof. Steve Conlon)
Presentation Outline
-
SPENN TATE1 8 5 5
VLRCOE Renewal Proposal (aka 5 year storm)
25 Separate Tasks31 PIs (PSU, PSU ARL, Michigan (1), UT Austin (1))40 Graduate Students5 years (20011-2016)$25M Total (12.5M from sponsor: NRTC = Army + Navy + NASA)
Partners (proposal cost share)LORD Corp SikorskyGoodrich BellTimken Aerospace GyrodyneMagCanica Inc Penn State University
Group Highlights
-
SPENN TATE1 8 5 5
Aeromechanics: More Speed, More fuel efficiency, all weatherUnsteady Airfoil Design MethodsRotor Hub Flows > Drag reductionNew Rotorcraft Airfoil Design ConceptsIcing Physics, Modeling, Detection
Structures: Lower weight, more reliability, safetyNanotailored Composites> Improved Toughness and Thermal
ConductivityNovel SMA Based Energy AbsorbersInterfacial Fracture and Functional Grading > Ultrasonic DeicingFrequency Selective Rotor Lag Damping
Flight Dynamics & control: autonomy, safety, new configsAutonomous Multi-Lift SystemsLoad Limiting Flight Controls for Co-axial Rotors
Group Highlights: VLRCOE Renewal tasks
-
SPENN TATE1 8 5 5
Design Concepts: Speed, range, altitudeMorphing Rotor Blades and WingsAeroelastically Tailored wing extensions and Winglets
> Large Civil TiltrotorsControl Redundancy> Perf, HQ, and SurvivabilityReduced Actuation Reqs and HQ of Swashplateless Rotors
Vibration & Noise Control: active rotors, variable rotors, speedFund Physics of Active Rotors > Perf and AcousticsMulti-functional Trailing edge FlapsTunable Fluidlastic Structures > Vib control & energy harvestMultifunctional Fluidlastic Picth Links> active rotors, energy harvest, loads
control
Group Highlights: VLRCOE Renewal tasks
-
SPENN TATE1 8 5 5
Propulsion and Drive Systems: weight, reliability, interior noise reduction
Comprehensive Anal of Gearbox Loss of LubeGearbox Health Monitoring and Loads Management via Piezo-
magneto-elastic control systemsMultifunctional Radial Isolator > bearing HUMS and Noise Red
Affordability: condition-based maintenance, SHM, etcHealth Monitoring for Joints in Composite StructuresStructural Tailoring for High Sens Robust Damage Detection
Maritime Operations: shipboard ops, dynamic interface, slung loads, etc
Advanced Response Types and Cueing Systems for Naval Ops
Autonomous Shipboard Take-Off and Landing
Group Highlights: VLRCOE Renewal tasks
-
SPENN TATE1 8 5 5
Group Highlights
Individual Project Highlights
- Multi-State Damper: Design and Test- Ultrasonic Anti-Icing: Recent progress
- Airframe Structural Health Monitoring(Prof. Steve Conlon)
Presentation Outline
-
SPENN TATE1 8 5 5
Multi-State Lead-Lag Damper Development and Validation
Conor Marr, PhD Candidate, Penn StateZach Fuhrer, Senior Engineer, LORD Corporation
Edward C. Smith, Professor, Penn StateGeorge A. Lesieutre, Professor, Penn State
AHS International 67th Annual Forum and Technology DisplayTest and Evaluation ITuesday, May 3, 2011
-
SPENN TATE1 8 5 5
Objectives
Design, construct, and experimentally validate a first generation prototype of a passive or semi-active LORD Fluidlastic bypass damper that greatly reduces damper forces when damping is not required
An adaptable lag damper could greatly reduce the forces seen both by the damper and the blade and hub attachment points.
Longer damper life, smaller lower drag parts, lighter dampers
-
SPENN TATE1 8 5 5
Approach: Experiment
Design damper to meet damping requirements for a generic light helicopter
Reduce damper force by at least 50% via a bypass feature
Conduct a series of experimental bench tests to evaluate the damper performance with bypass channels open and closed
-
SPENN TATE1 8 5 5
Approach: Analysis
Predict damper behavior using basic analytical fluid flow equations
Develop a CFD model of the bypass damper
Validate models with experimental data
Use findings to work towards ultimate goal of developing a first-principles model that incorporates CFD correction factors
-
SPENN TATE1 8 5 5
Experimental Prototype
Parameter English MetricPiston
Diameter 2.74 in 0.07 m
Bypass Diameter 3 x 0.4 in 3 x 0.01 m
Adjustable number of orifices (max of 2) and orifice diameter
Bypass channels able to be open or closed
Adjustable number of bypass channels (max of 3)
Bypass inlet diameter alterable up to 0.4 inches in diameter
Closed state meets light helicopter damper requirements
-
SPENN TATE1 8 5 5
CFD Model
Bypass Channel
Annular Gap
PistonRestrictive
Orifice
Ansys Workbench meshing utility used to create geometry and mesh
Full 3 dimensional model
Fluent used to calculate fluid flow
Transient flow and dynamic meshing utilized
Carreau equation for shear thinning captures nonlinear fluid behavior:
( ) ( )( )
++=
2
12
inf0inf 1n
act
-
SPENN TATE1 8 5 5
CFD Results: Bypass Closed
Velocity Magnitude pictured over a single cycle for 2.5 Hz at 0.06 dynamic displacement
Closed bypass channel case
2D cross section of 3D calculation
Flow is almost exclusively through the orifice
-
SPENN TATE1 8 5 5
CFD Results: Bypass open
Velocity vectors at orifice and bypass entrance/exit
Flow is split between bypass channel and orifice
3 bypass channels with a diameter of 0.1 inches reduce damper force by approximately 50%
-
SPENN TATE1 8 5 5
Results: Comparison with CFD
4 Hz at 0.06 Bypass Closed
CFD Model: 10% error for Peak Force, 15% error for Loss Stiffness
Analytical Model: 45% error for Peak Force, 82% error for Loss Stiffness
-1500
-1000
-500
0
500
1000
1500
-0.08 -0.06 -0.04 -0.02 0 0.02 0.04 0.06 0.08
Position (in)
Forc
e (lb
f) Experiment
CFD
Analytical
-
SPENN TATE1 8 5 5
Results: Comparison with CFD
2.5 Hz at 0.06 Bypass Open
-300
-200
-100
0
100
200
300
-0.08 -0.06 -0.04 -0.02 0 0.02 0.04 0.06 0.08
Position (in)
Forc
e (lb
f) Experiment
CFD
Analytical
Both CFD and Analytical models predict a near elimination of damping when three 0.4 diameter bypass channels are opened
-
SPENN TATE1 8 5 5
Results: Comparison with CFD
2.5 Hz at 0.06 Bypass Open
-300
-200
-100
0
100
200
300
-0.08 -0.06 -0.04 -0.02 0 0.02 0.04 0.06 0.08
Position (in)
Forc
e (lb
f) Experiment
CFD
Analytical
Main source of error due to lack of damping from the elastomerin the CFD and analytical models
-
SPENN TATE1 8 5 5
Ultrasonic De-Icing Concept
CF
DragIce
Leading Edge Protection Cap
Piezoelectric actuators used to create ultrasonic waves which generate transverse shear stresses at the ice interface
a
a
-
SPENN TATE1 8 5 5
Ultrasonic De-Icing Concept
CF
DragIce
Leading Edge Protection Cap
Piezoelectric actuators used to create ultrasonic waves which generate transverse shear stresses at the ice interface
a
Leading Edge Mass (10 20% Weight of the Blade)
a
1
Substitute with Active Piezoelectric Material
2
aa
-
SPENN TATE1 8 5 5
Ultrasonic De-Icing Issues
Issue Proposed SolutionLimited control of matching ultrasonic modes
Actuator Cracking Failure
Actuator Debonding
PZT Actuation Controller
Drive Actuators in Compression
Optimal Thickness Actuators
-
SPENN TATE1 8 5 5
PZT Actuation Controller Design
Design Goal: Develop a program to autonomously check the ultrasonic modes of a PZT actuator and drive the actuator at the optimum ultrasonic mode
Variations in Ultrasonic Modes due to:
Loading ConditionsAmbient TemperatureActuator TemperatureBoundary Conditions
-
SPENN TATE1 8 5 5
Thickness Reduction
Predicted thinner actuators would not delaminate due to lower inertia forces
Modeled 0.10 vs. 0.05 Thick Disk Actuators to compare transverse shear stresses at the PZT/Glue interface
EP 21 Adhesive- 0.01 Thick=1078 kg/m3E=2240 MPa, =0.3
PZT-4 Disk 1.5 Diameter
Ti Plate 6x6x0.04
70 V
140 VApplied Voltage
-
SPENN TATE1 8 5 5
Thickness Reduction
-
SPENN TATE1 8 5 5
Thickness Reduction
-
SPENN TATE1 8 5 5
Rotational Test Setup
~NACA 0024, 6 Chord
Outer Airfoil: NACA 0015, 16 Chord
23.5
12
5
Test Specimen
Taper Section
Grip Attachment
Test Specimen: 12 Span, 16 Chord, NACA 0015 AirfoilInterchange leading edge cap/actuation systems
Ultrasonic Deicing System Tested on Representative Leading Edge Erosion Cap
Thin PZT-4 Disk1.5 Diameter, 0.05 Thickness (x12)Total Volume = 1.07 in2Radial Mode Frequency = 65-66 kHz
-
SPENN TATE1 8 5 5
Ice Accretion (2mm)
NACA 0015 Ti Leading Edge Erosion Cap
10.6 cm
Finite Element Model Setup
-
SPENN TATE1 8 5 5
Finite Element Results
Transverse shear stresses at the ice interface exceed published results for the adhesion strength of Ice-Ti (250kPa-875kPa)
-
SPENN TATE1 8 5 5
Finite Element Results
Transverse shear stresses at the ice interface exceed published results for the adhesion strength of Ice-Ti (250kPa-875kPa)
-
SPENN TATE1 8 5 5
Rotational Test Matrix
A total of 4 Impact Icing Test Conducted
Tested at 2 Temperatures (-12 C, -18 C)
Constants RPM: 320 MVD: ~25 m LWC: ~3.5 g/m3
Total icing time dictated by the rotor imbalance load limitations
The Ice Thickness measured on Blade without ultrasonic deicing system
-
SPENN TATE1 8 5 5
Rotational Test Matrix
-
SPENN TATE1 8 5 5
Sample Results: Case 4
Icing ConditionsTemp: -18.2 CMVD: ~25 mLWC: ~3.5 g/m3RPM: 320
No Ultrasonic De-Icing System Ice Thickness: 0.431
Ultrasonic De-Icing SystemPower: 1.48 W/in2Deicing Time : 139 s
-
SPENN TATE1 8 5 5
Sample Results: Case 4
Icing ConditionsTemp: -18.2 CMVD: ~25 mLWC: ~3.5 g/m3RPM: 320
No Ultrasonic De-Icing System Ultrasonic De-Icing SystemPower: 1.48 W/in2Deicing Time : 139 s
Heaters to Prevent Ice Bridging to Test Section
-
SPENN TATE1 8 5 5
Group Highlights
Preparation and Submission of 2011-2016 VLRCOE Renewal Proposal
Individual Project Highlights
- Multi-State Damper: Design and Test- Ultrasonic Anti-Icing: Recent progress
- Airframe Structural Health Monitoring(Prof. Steve Conlon)
Presentation Outline
-
ARLPenn State
1
Overview of Recent Rotorcraft Structural Health Monitoring
/ Damage Detection Research Activity
9 May 2011
Center for Acoustics & Vibration
20th Annual Spring Workshop
Penn State Vertical Lift Research Center of Excellence
Stephen C. ConlonResearch Associate Applied Research Laboratory
Associate Director Vertical Lift Research Center of Excellence814-863-9894
-
ARLPenn State
2
Recent & OngoingSHM / CBM Projects
6.1 (SHM / Damage Detection)Rotor blade damage detection (CRI, 3 yrs)SI based damage detection (CRI, 2 yrs)
6.2 (SHM / Damage Detection)Intensity based airframe SHM (AATD, 2 yr)
6.2+ (SHM)OH-58D Tailboom damage detection study (PEO, 6 mo)
-
ARLPenn State
3
Recent SHM Developments
Airframe SHM Technology Development Overview:
1. Airframe Intensity Based Structural Health Monitoring, Aviation Applied Technology Directorate (AATD) U. S. Army Research, Development and Engineering Command Ft. Eustis, Virginia
2. OH-58 Tailboom Damage Detection Study, PEO US Army Aviation & Missile Command, SFAE-AV-ASH-KW, Redstone Arsenal
-
ARLPenn State
4
3f
Nonlinear Vibration Based Damage Detection
2 f 3 f
f
Considering a cracked rod subjected to an external dynamic axial load:
52
f32
f2f
Subharmonics and Ultra-subharmonics
The Subharmonics components are characterized by a threshold behavior, - they are not generated below a certain amplitude of the external driving force.
f
F. Semperlotti, K.W. Wang, E. C. Smith, Identification of the location of a breathing crack using super-harmonic response signals due to system nonlinearity, AIAA J., 47 (9), (2009).
-
ARLPenn State
5
Structural Intensity Based Damage Detection
Point source
Point sink
dB (r
e 1
Wat
t/N)
SI maps of plate driven at resonance frequencies
Frequency sweep from 135 Hz to 695 Hz, color bar indicated SI magnitude in dB, unit vectors indicate SI direction
(Damaged Structure)
For SHM implementation local sensors / sensor arrays will detect damaged induced changes to SI magnitude and direction
-
ARLPenn State
6
Damage source
Point sink
Damage source
Point sink
Source due to harmonic distortion in drive / actuator system
xxxx
Frequency
Nonlinear Structural Intensity Based Damage Detection
Damaged Structure: Sub-harmonic vs Super-harmonic Vibration
The resonance growth of the modes is affected by the amplitude and frequency hysteresis & instability
Contact Acoustic Nonlinearity (CAN)Excitation Frequency
2f
F. Semperlotti and S.C. Conlon, Structural damage identification in plates via Nonlinear Structural Intensity maps, Journal of the Acoustical Society of America 127(2), EL48-EL53, 2010.
F. Semperlotti and S. C. Conlon, Nonlinear structural surface intensity: an application of contact acoustic nonlinearity to power flow based damage detection, Appl. Phys. Lett., 97, (2010)
-
ARLPenn State
7
Intensity Based Structural Health MonitoringTechnology Discussion
Issue:Rotorcraft airframe elements can experience critical fatigue loading during their usage life. The development and implementation of enhanced structural diagnostics techniques will directly support the Army Aviation S&T Mission
Objectives:Structural intensity based SHM approach for airframe structural damage detection was investigated
Program Solution:Study the fundamental energy flow mechanisms of vibrating structures
Develop simulation & experimental techniques to determine sensitivities for detecting and localizing structural damage
Apply techniques to representative rotorcraft airframe structure / typical damage flaws for detection performance validation
-
ARLPenn State
8
Structural Intensity BasedSHM System Overview
-
ARLPenn State
9
Why Airframe Structural Health Monitoring?
Goal of SHM development:
Develop technologies to provide critical actionable information, enabling a shift to airframe CBM
UH-60 Corrosion & Crack Locations Airframe and propulsion are
largest cost drivers
Inspection Activities
-
ARLPenn State
10
UH-60 Transmission Frame Primary Structural Element Cracking
Typical application of interest for Intensity Based SHM
Damage precursors fastener (rivets) loosening / damage, load / stress redistribution
Structure (frame strap) fatigue crack initiation & growth
Transmission Support and Attachment Structure
Region of interest: FS360 / BL 16.5
FS360
Fwd
(J.Cycon , SHM Activities and Needs for Sikorsky Products,PSU SHM Center of Excellence Meeting , Nov 2007)
-
ARLPenn State
11
Development and Verification / Validation Test Beds
d)
c)
a&b)
Incr
easi
ng C
ompl
exity
Plate & stiffened plate Study/insight SI for healthy &
damaged structures Discrete sensor development
/ implementation Algorithm development Detection performance V&V
Transmission frame joint mock-up
Technology transition to more complex substructure
Detection performance V&V
UH-60 upper cabin structure
Technology transition to airframe complex structure
Detection performance V&V
Structural Complexity
Homogeneous plate
Plate + stiffener
I-beam frame structure
Joint strap w/ fasteners
Real aircraft structure Skin Stiffeners / ribs Riveted joints
-
ARLPenn State
12
Verification and Validation Test Beds: Transmission Frame Mock-up
Transmission Support and Attachment Structure
Example - critical region of interest: FS360 / BL 16.5
FS360Electrodynamic shaker (out-of-plane excitation)
PZT actuator (in-plane excitation)
Straps loose fastener progression and strap crack progression for damage detection measurements
-
ARLPenn State
13
Verification and Validation Test Beds: UH-60 Upper Cabin Structure
Transmission Support and Attachment Structure
Example - critical region of interest: FS360 / BL 16.5
Fwd
(~ 8 ft)
Technology transition to airframe complex structure
Detection performance V&V
-
ARLPenn State
14
xxxx
Frequency
UH-60 Roof Section:Nonlinear Structural Surface Intensity
Active InterrogationNSSI exploits the nonlinear response characteristics of certain types of defects such as fatigue cracks and loose riveted joints.
Damage
Interrogation Signal
(Shaker)
Nonlinear Harmonics
The interrogation signal (single tone continuous excitation) triggers the damage nonlinear dynamic response at subharmonic frequencies.
-
ARLPenn State
15
Structural Intensity Based SHM System: Application Results
Transmission Frame Test Structure UH-60 Upper Cabin Test Structure
Damage detection at all 4 corner joints on frame using single SSI sensor location, drive frequency approx. 2.48 kHz
x x x x
xx
Damage detection loose fasteners, BW 1.75 to 1.85 kHz
Damage discrimination, loose fastener vs crack, BW 5.5 to 5.8 kHz
Sensor to damage distance:Upper left < 6 inchUpper right = 33 inchLower right = 66 inch (path)
NSSI Feature
(Condition Indicator)
12 dB
16 dB10 dB
25 dB
F. Semperlotti, S. Conlon, and A. Barnard, Airframe Structural Damage Detection: A Nonlinear Structural Surface Intensity basedtechnique, Journal of the Acoustical Society of America 129(4), EL121-EL127, 2011.
-
ARLPenn State
16
OH58 Tailboom Damage Detection StudyTechnology Discussion
Issue:Fleet OH-58s are experiencing tailboom cracking / damage which requires inspections every 10 hrs
Objectives:Nonlinear intensity based SHM approach for airframestructural damage detection is being investigated
Program Solution:Transition / enhance NSSI techniques developed under 6.2 AATD effort
Apply & adapt experimental techniques to laboratory test beds for demonstrating detection capability (NSSI sensors & actuators)
Assess (1) use of current HUMS sensors/locations for damage detection use, (2) in-flight passive SHM
Define system technology transition plan / aircraft integration requirements for 6.3 Phase II effort
(Phase II) Deploy techniques to OH58 airframe structure / typical damage flaws for detection performance validation and system flight qualification
-
ARLPenn State
17
Tailboom SHM Testbeds
-
ARLPenn State
18
Damage grouped around several hot spots - hanger bearing mounts, tailboom mounts, gearbox mount
Crack
Working Rivet/Hardware
Golden Rivet
Maintenance/Damage
Other
OH58 Tailboom Damage Data Base Review
Inspection area is one inch either side and
3 inches above and below golden rivet
Designated inspection
area captures 10% of cracks
-
ARLPenn State
19
OH-58D HUMS
ACC 12HB #6
ACC 11HB #5
ACC 10HB #4
ACC 9HB #3 ACC 8
HB #2 ACC 7HB #1
ACC 5Tail GBX Axial
TAC 2Tail Rotor
ACC 4Tail GBX Radial
Honeywell CBM for KW has 15 Accelerometers and 5 Tachometers covering all
the rotating drive train components
ACC 1Fore/Aft
ACC 2Vertical
ACC 18Input Quill
TAC 3NR
TAC 1Main RotorACC 17XMSN
Mast Bearing
ACC 13Engine
Compress
TAC 5NGTAC 4
NP
ACC 14Engine GB
ACC 15Engine Turbine
Existing HUMS accelerometers potential for use / integration with embedded Tailboom SHM system
-
ARLPenn State
20
SHM Technology Development and Verification / Validation Test Beds
Plates & Connected Plates
Discrete sensor & algorithm development / implementation
Fatigue crack detection performance
OH-58 Tailboom Structures
Technology transition to airframe complex structure
Algorithm development Detection performance V&V
Structural Complexity
Homogeneous plate
Plate + lap joint / fastener line
Real aircraft structure Skin, conical
shell Stiffeners / ribs Riveted joints
Incr
easi
ng C
ompl
exity
-
ARLPenn State
21
Structural Intensity Based SHM System Damage Detection: APPLICATION RESULTS
OH-58D Test Structure Aluminum Skin (Fatigue Crack) Test Structures
Damage detection, exposed and hidden small fatigue cracks
Detection with actuator position both local & remote (through lap-joint)
High damage detection sensitivity - loose HB bracket: NSSI (bulkhead sensors), NLS (skin mounted), NLA (HUMS accels at brackets)
Good vibration response from skin & bulkhead mounted PZT actuators
Crack (hidden by joint)
Fastener line / lap joint
30 dB
20 dB
20 dB
-
ARLPenn State
22
Penn StateSHM Team
S. Conlon (ARL/Aero Eng), E. Smith (Aero Eng), J. Banks (ARL), S. Evans (Aero Eng)
F. Semperlotti (Ph.D., UMich), P. Romano (M.S., Bell), W. Schmidt (M.S., Sikorsky), B. Grisso (Post Doc, NSWC
Carderock), K. Brennan (M.S.)
M. Shepherd (ARL), J. Hines (ARL), A. Barnard (ARL), K. Reichard (ARL/Acoustics), S. Hambric (ARL/Acoustics)
J. Cote (B.S., Pratt & Whitney), P. DiBiase (B.S., NAVAIR Pax River), Justin Long (B.S.)
CAVWorkshop11_newSlide Number 1Interaction with Other PSU Research CentersVertical Lift Center Tech BaseSlide Number 4Slide Number 5Slide Number 6Slide Number 7Slide Number 8Slide Number 9Slide Number 10Slide Number 11Slide Number 12Slide Number 13Slide Number 14Slide Number 15Slide Number 16Slide Number 17Slide Number 18Slide Number 19Slide Number 20Slide Number 21Ultrasonic De-Icing ConceptUltrasonic De-Icing ConceptUltrasonic De-Icing IssuesPZT Actuation Controller DesignThickness ReductionThickness ReductionThickness ReductionRotational Test SetupFinite Element Model SetupFinite Element ResultsFinite Element ResultsRotational Test MatrixRotational Test MatrixSample Results: Case 4Sample Results: Case 4Slide Number 37
CAV_rotrcraft_SHM_2011_scc_postSlide Number 1Recent & OngoingSHM / CBM Projects Recent SHM DevelopmentsNonlinear Vibration Based Damage DetectionStructural Intensity Based Damage DetectionNonlinear Structural Intensity Based Damage DetectionIntensity Based Structural Health MonitoringTechnology DiscussionStructural Intensity BasedSHM System OverviewWhy Airframe Structural Health Monitoring?UH-60 Transmission Frame Primary Structural Element CrackingDevelopment and Verification / Validation Test BedsVerification and Validation Test Beds: Transmission Frame Mock-upVerification and Validation Test Beds: UH-60 Upper Cabin StructureSlide Number 14Structural Intensity Based SHM System: Application ResultsOH58 Tailboom Damage Detection StudyTechnology DiscussionTailboom SHM TestbedsSlide Number 18OH-58D HUMSSHM Technology Development and Verification / Validation Test BedsStructural Intensity Based SHM System Damage Detection: APPLICATION RESULTS Penn StateSHM Team