Dr. George Y. Baaklini Profile

Dr. George Y. Baaklini

Sr. Research Scientist at NASA Glenn Research Ctr

SPIE Involvement:

Author

Publications (28)

Proceedings Article | 27 March 2015 Paper

Engine rotor health monitoring: an experimental approach to fault detection and durability assessment

Ali Abdul-Aziz, Mark Woike, Michelle Clem, George Baaklini

Proceedings Volume 9436, 94360A (2015) https://doi.org/10.1117/12.2087602

KEYWORDS: Sensors, Microwave radiation, Safety, Data acquisition, Finite element methods, Manufacturing, Structural health monitoring, Detector development, Sensor technology, 3D modeling

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Efforts to update and improve turbine engine components in meeting flights safety and durability requirements are commitments that engine manufacturers try to continuously fulfill. Most of their concerns and developments energies focus on the rotating components as rotor disks. These components typically undergo rigorous operating conditions and are subject to high centrifugal loadings which subject them to various failure mechanisms. Thus, developing highly advanced health monitoring technology to screen their efficacy and performance is very essential to their prolonged service life and operational success. Nondestructive evaluation techniques are among the many screening methods that presently are being used to pre-detect hidden flaws and mini cracks prior to any appalling events occurrence. Most of these methods or procedures are confined to evaluating material’s discontinuities and other defects that have mature to a point where failure is eminent. Hence, development of more robust techniques to pre-predict faults prior to any catastrophic events in these components is highly vital. This paper is focused on presenting research activities covering the ongoing research efforts at NASA Glenn Research Center (GRC) rotor dynamics laboratory in support of developing a fault detection system for key critical turbine engine components. Data obtained from spin test experiments of a rotor disk that relates to investigating behavior of blade tip clearance, tip timing and shaft displacement based on measured data acquired from sensor devices such as eddy current, capacitive and microwave are presented. Additional results linking test data with finite element modeling to characterize the structural durability of a cracked rotor as it relays to the experimental tests and findings is also presented. An obvious difference in the vibration response is shown between the notched and the baseline no notch rotor disk indicating the presence of some type of irregularity.

Proceedings Article | 17 April 2014 Paper

Turbine engine rotor health monitoring evaluation by means of finite element analyses and spin tests data

Ali Abdul-Aziz, Mark Woike, Michelle Clem, George Baaklini

Proceedings Volume 9062, 90620M (2014) https://doi.org/10.1117/12.2046373

KEYWORDS: Sensors, Finite element methods, Analytical research, Data modeling, Safety, Microwave radiation, 3D modeling, Failure analysis, Sensor technology, Nondestructive evaluation

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Proceedings Article | 11 April 2013 Paper

Turbine engine rotor health monitoring and durability evaluation using spin tests data

Ali Abdul-Aziz, Mark Woike, Michelle Clem, George Baaklini

Proceedings Volume 8693, 86930N (2013) https://doi.org/10.1117/12.2008978

KEYWORDS: Sensors, Analytical research, Safety, Nondestructive evaluation, Manufacturing, Data modeling, Sensor technology, Inspection, Mathematical modeling, Product engineering

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Proceedings Article | 30 March 2012 Paper

Turbine engine disk rotor health monitoring assessment using spin tests data

Ali Abdul-Aziz, Mark Woike, George Baaklini, James Bodis

Proceedings Volume 8346, 834616 (2012) https://doi.org/10.1117/12.912524

KEYWORDS: Sensors, Microwave radiation, Electronics, Sensor technology, Safety, Nondestructive evaluation, Structural health monitoring, Capacitance, Distance measurement, Environmental sensing

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Proceedings Article | 9 April 2010 Paper

Propulsion health monitoring of a turbine engine disk using spin test data

Ali Abdul-Aziz, Mark Woike, Nikunj Oza, Bryan Matthews, George Baakilini

Proceedings Volume 7650, 76501B (2010) https://doi.org/10.1117/12.847574

KEYWORDS: Sensors, Data modeling, Detection and tracking algorithms, Sensor technology, Safety, Analytical research, Nondestructive evaluation, Inspection, Capacitance, Environmental monitoring

Read Abstract +

On line detection techniques to monitor the health of rotating engine components are becoming increasingly attractive options to aircraft engine companies in order to increase safety of operation and lower maintenance costs. Health monitoring remains a challenging feature to easily implement, especially, in the presence of scattered loading conditions, crack size, component geometry and materials properties. The current trend, however, is to utilize noninvasive types of health monitoring or nondestructive techniques to detect hidden flaws and mini cracks before any catastrophic event occurs. These techniques go further to evaluate materials' discontinuities and other anomalies that have grown to the level of critical defects which can lead to failure. Generally, health monitoring is highly dependent on sensor systems that are capable of performing in various engine environmental conditions and able to transmit a signal upon a predetermined crack length, while acting in a neutral form upon the overall performance of the engine system. Efforts are under way at NASA Glenn Research Center through support of the Intelligent Vehicle Health Management Project (IVHM) to develop and implement such sensor technology for a wide variety of applications. These efforts are focused on developing high temperature, wireless, low cost and durable products. Therefore, in an effort to address the technical issues concerning health monitoring of a rotor disk, this paper considers data collected from an experimental study using high frequency capacitive sensor technology to capture blade tip clearance and tip timing measurements in a rotating engine-like-disk-to predict the disk faults and assess its structural integrity. The experimental results collected at a range of rotational speeds from tests conducted at the NASA Glenn Research Center's Rotordynamics Laboratory will be evaluated using multiple data-driven anomaly detection techniques to identify anomalies in the disk. This study is expected to present a select evaluation of online health monitoring of a rotating disk using these high caliber sensors and test the capability of the in-house spin system.

Proceedings Article | 8 April 2009 Paper

NDE using sensor based approach to propulsion health monitoring of a turbine engine disk

Ali Abdul-Aziz, Mark Woike, G. Abumeri, John Lekki, George Baaklini

Proceedings Volume 7295, 729505 (2009) https://doi.org/10.1117/12.815494

KEYWORDS: Failure analysis, Nondestructive evaluation, Sensors, Finite element methods, Safety, Mechanics, Data modeling, Inspection, Analytical research, Image filtering

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Proceedings Article | 29 March 2006 Paper

Finite element design study of a bladed flat rotating disk to simulate cracking in a typical turbine disk: Part II

Ali Abdul-Aziz, Jeffrey Trudell, George Baakilini

Proceedings Volume 6176, 61760J (2006) https://doi.org/10.1117/12.649802

KEYWORDS: Safety, Curium, Finite element methods, Nondestructive evaluation, Sensors, Damage detection, Reliability, Sensing systems, Aerospace engineering, Nickel

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Proceedings Article | 19 May 2005 Paper

Application of nonlinear dynamics tools for diagnosis of cracked rotor vibration signatures

Jerzy Sawicki, Xi Wu, Andrew Gyekenyesi, George Baaklini

Proceedings Volume 5767, (2005) https://doi.org/10.1117/12.601788

KEYWORDS: Nonlinear dynamics, Complex systems, Dynamical systems, Tellurium, Mechanical engineering, Transducers, Finite element methods, Anisotropy, Nondestructive evaluation, Aerospace engineering

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Proceedings Article | 19 May 2005 Paper

Finite element design study of a bladed, flat rotating disk to simulate cracking in a typical turbine disk

Ali Abdul-Aziz, Jeffrey Trudell, George Baaklini

Proceedings Volume 5767, (2005) https://doi.org/10.1117/12.601896

KEYWORDS: Nondestructive evaluation, Safety, Finite element methods, Chemical elements, Sensing systems, Signal detection, Inspection, Aerospace engineering, Nickel, Sensors

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Proceedings Article | 9 May 2005 Paper

Structural damage assessment of propulsion system components by impedance based health monitoring

Richard Martin, Andrew Gyekneyesi, Jerzy Sawicki, George Baaklini

Proceedings Volume 5770, (2005) https://doi.org/10.1117/12.602110

KEYWORDS: Ferroelectric materials, Structural health monitoring, Sensors, Nondestructive evaluation, Aluminum, Damage detection, Inspection, Data acquisition, Software development, Ultrasonics

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Proceedings Article | 20 July 2004 Paper

A combined NDE-fatigue testing and three-dimensional image processing study of a SiC/SiC composite system

Ali Abdul-Aziz, Louis Ghosn, George Baaklini, Richard Rauser, John Zima

Proceedings Volume 5393, (2004) https://doi.org/10.1117/12.538241

KEYWORDS: Composites, Computed tomography, Nondestructive evaluation, 3D image processing, Image processing, Silicon carbide, 3D modeling, X-ray computed tomography, Ceramics, Coating

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Non destructive evaluation (NDE) is a critical technology for improving the quality of a component in a cost-sparing production environment. NDE detects variations in a material or a component without altering or damaging the test piece. Using these techniques to improve the production process requires characterization of the faults and their influence on the component performance. This task depends on the material properties and on the complexity of the component geometry. Hence, the NDE technique is applied to study the structural durability of ceramic matrix composite materials used in gas turbine engine applications. Matrix voids are common anomalies generated during the melt infiltration process. The effects of these matrix porosities are usually associated with a reduction in the initial overall composite stiffness and an increase in the thermal conductivity of the component. Furthermore, since the role of the matrix as well as the coating is to protect the fibers from the harsh engine environments, the current design approach is to limit the design stress level of CMC components to always be below the first matrix cracking stress. In this study, the effect of matrix porosity on the matrix cracking stress is evaluated using a combined fatigue tensile testing, NDE, and 3 D image processing approach. Computed Tomography (CT) is utilized as the NDE technique to characterize the initial matrix porosity’s locations and sizes in various CMC test specimens. The three dimensional volume rendering approach is exercised to construct the 3 D volume of the specimen based on the geometric modeling of the specimen's CT results using image analysis and geometric modeling software. The same scanned specimens are then fatigue tested to various maximum loads and temperatures to depict the matrix cracking locations in relation to the initial damage. The specimen are then re-scanned and checked for further anomalies and obvious changes in the damage state. Finally, rendered volumes of the gauge region of the specimen is generated and observed to check damage progression with increasing cycles. Observations and critical findings related to this material are reported.

Proceedings Article | 20 July 2004 Paper

Analysis of transient response of cracked flexible rotor

Jerzy Sawicki, Andrew Gyekenyesi, George Baaklini

Proceedings Volume 5393, (2004) https://doi.org/10.1117/12.547996

KEYWORDS: Tantalum, Analytical research, Roads, Matrices, Mechanical engineering, Mathematical modeling, Nondestructive evaluation, Aerospace engineering, Composites, Motion models

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Proceedings Article | 1 August 2003 Paper

Acousto-ultrasonic characterization of C/SiC composites under different loading configurations

Laura Cosgriff, Richard Martin, George Baaklini

Proceedings Volume 5046, (2003) https://doi.org/10.1117/12.484292

KEYWORDS: Ultrasonics, Transducers, Composites, Statistical analysis, Nondestructive evaluation, Error analysis, Ceramics, Carbon, Silicon carbide, Material characterization

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Proceedings Article | 1 August 2003 Paper

Combined NDE/finite element technique to study the effects of matrix porosity in the behavior of ceramic matrix composites

Ali Abdul-Aziz, Louis Ghosn, George Baaklini, Ramakrishna Bhatt

Proceedings Volume 5046, (2003) https://doi.org/10.1117/12.484775

KEYWORDS: Computed tomography, 3D modeling, Finite element methods, Composites, Ceramics, 3D image processing, Nondestructive evaluation, Coating, X-ray computed tomography, Roads

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Proceedings Article | 1 August 2003 Paper

Comparison of acoustography, ultrasonic spectroscopy, and c-scan ultrasonics as applied to the composite flywheels

Honghui Wang, Richard Martin, George Baaklini, Jaswinder Sandhu

Proceedings Volume 5046, (2003) https://doi.org/10.1117/12.488052

KEYWORDS: Ultrasonics, Spectroscopy, Nondestructive evaluation, Image quality standards, Acousto-optics, Sensors, Composites, Inspection, Ultrasonography, Imaging spectroscopy

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Proceedings Article | 1 August 2003 Paper

Vibration-based crack diagnosis in rotating shafts during acceleration through resonance

Jerzy Sawicki, Xi Wu, George Baaklini, Andrew Gyekenyesi

Proceedings Volume 5046, (2003) https://doi.org/10.1117/12.484297

KEYWORDS: Motion models, Nondestructive evaluation, Systems modeling, Roads, Nomenclature, Dynamical systems, Analytical research, Safety, Inspection, Vibrometry

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Proceedings Article | 18 June 2002 Paper

Nondestructive evaluation of ceramic matrix composites coupled with finite element analyses

Ali Abdul-Aziz, George Baaklini, Ramakrishna Bhatt

Proceedings Volume 4704, (2002) https://doi.org/10.1117/12.470733

KEYWORDS: 3D modeling, Computed tomography, Finite element methods, 3D image processing, Nondestructive evaluation, Solid modeling, Composites, Ceramics, Failure analysis, Data modeling

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Proceedings Article | 18 June 2002 Paper

Investigations of delaminations with ultrasonic spectroscopy

Laura Harmon, Andrew Gyekenyesi, Richard Martin, George Baaklini

Proceedings Volume 4704, (2002) https://doi.org/10.1117/12.470722

KEYWORDS: Ultrasonics, Spectroscopy, Transducers, Composites, Nondestructive evaluation, Ultrasonography, Polymers, Acoustics, Computing systems, Aerospace engineering

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Proceedings Article | 18 June 2002 Paper

Modal-based diagnostics of cracked rotors

Jerzy Sawicki, Andrew Gyekenyesi, George Baaklini

Proceedings Volume 4704, (2002) https://doi.org/10.1117/12.470718

KEYWORDS: Sensors, Nondestructive evaluation, Matrices, Actuators, Diagnostics, Neodymium, Damage detection, Manufacturing, Data modeling, Roads

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Proceedings Article | 3 August 2001 Paper

Integrated NDE and FEM characterization of composite rotors

Ali Abdul-Aziz, George Baaklini, Jeffrey Trudell

Proceedings Volume 4336, (2001) https://doi.org/10.1117/12.435574

KEYWORDS: Finite element methods, Nondestructive evaluation, Composites, Mechanics, Computed tomography, Chemical elements, 3D modeling, Solids, Stress analysis, Structural analysis

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Proceedings Article | 3 August 2001 Paper

Scanning ultrasonic spectroscopy for composite flywheels

Richard Martin, George Baaklini

Proceedings Volume 4336, (2001) https://doi.org/10.1117/12.435573

KEYWORDS: Ultrasonics, Spectroscopy, Composites, Nondestructive evaluation, Transducers, Data acquisition, Inspection, Standards development, Acoustics, Control systems

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Proceedings Article | 3 August 2001 Paper

Rotor health monitoring and damage detection utilizing a disk spin simulation system

Andrew Gyekenyesi, George Baaklini

Proceedings Volume 4336, (2001) https://doi.org/10.1117/12.435562

KEYWORDS: Sensors, Teeth, Information operations, Nondestructive evaluation, Damage detection, Sensing systems, Titanium, Calibration, Fluctuations and noise, Data modeling

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Proceedings Article | 3 August 2001 Paper

Ultrasonic resonance spectroscopy of composite rings for flywheel rotors

Laura Harmon, George Baaklini

Proceedings Volume 4336, (2001) https://doi.org/10.1117/12.435568

KEYWORDS: Composites, Ultrasonics, Spectroscopy, Acoustics, Manufacturing, Transducers, Nondestructive evaluation, Multilayers, Fourier transforms, Spectroscopes

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Proceedings Article | 13 May 2000 Paper

Quantifying residual stresses by means of thermoelastic stress analysis

Andrew Gyekenyesi, George Baaklini

Proceedings Volume 3993, (2000) https://doi.org/10.1117/12.385479

KEYWORDS: Temperature metrology, Cameras, Sensors, Stress analysis, Infrared cameras, Titanium, Nickel, Imaging systems, Electronics, Infrared imaging

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Proceedings Article | 13 May 2000 Paper

Challenges in integrating nondestructive evaluation and finite-element methods for realistic structural analysis

Ali Abdul-Aziz, George Baaklini, Dmitri Zagidulin, Richard Rauser

Proceedings Volume 3993, (2000) https://doi.org/10.1117/12.385504

KEYWORDS: 3D modeling, Computed tomography, Finite element methods, Nondestructive evaluation, Composites, 3D image processing, Image filtering, Metals, Image processing, Solid modeling

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Proceedings Article | 8 February 1999 Paper

Thermoelastic stress analysis: the mean stress effect in metallic alloys

Andrew Gyekenyesi, George Baaklini

Proceedings Volume 3585, (1999) https://doi.org/10.1117/12.339842

KEYWORDS: Cameras, Stress analysis, Temperature metrology, Titanium, Sensors, Nickel, Imaging systems, Infrared cameras, Error analysis, Calibration

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Proceedings Article | 15 November 1996 Paper

Structural characterization of metal-matrix composites using computed tomography data

Robert Yancey, Roosevelt Gibson, George Baaklini

Proceedings Volume 2944, (1996) https://doi.org/10.1117/12.259042

KEYWORDS: Computed tomography, Image segmentation, Composites, Data centers, Image analysis, Titanium, Visualization, Binary data, Image filtering, Nondestructive evaluation

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Proceedings Article | 16 December 1993 Paper

Advanced composites characterization with x-ray technologies

George Baaklini

Proceedings Volume 2009, (1993) https://doi.org/10.1117/12.164740

KEYWORDS: Composites, Radiography, X-rays, Manufacturing, X-ray computed tomography, Nondestructive evaluation, X-ray detectors, X-ray technology, Systems modeling, Ceramics

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Showing 5 of 28 publications

Proceedings Volume Editor (12)

SPIE Conference Volume | 16 March 2006

Testing, Reliability, and Application of Micro- and Nano-Material Systems IV

SPIE Conference Volume | 16 March 2006

Advanced Sensor Technologies for Nondestructive Evaluation and Structural Health Monitoring II

SPIE Conference Volume | 9 May 2005

Testing, Reliability, and Application of Micro- and Nano-Material Systems III

SPIE Conference Volume | 9 May 2005

Advanced Sensor Technologies for Nondestructive Evaluation and Structural Health Monitoring

SPIE Conference Volume | 21 July 2004

Testing, Reliability, and Application of Micro- and Nano-Material Systems II

Showing 5 of 12 publications

Conference Committee Involvement (49)

NDE 4.0 and Smart Structures for Industry, Smart Cities, Communication, and Energy

8 March 2021 | Online Only, California, United States

Smart Structures and NDE for Industry 4.0, Smart Cities, and Energy Systems

27 April 2020 | Online Only, California, United States

Smart Structures and NDE for Energy Systems and Industry 4.0

4 March 2019 | Denver, Colorado, United States

Smart Materials and Nondestructive Evaluation for Energy Systems IV

5 March 2018 | Denver, Colorado, United States

Smart Materials and Nondestructive Evaluation for Energy Systems III

27 March 2017 | Portland, Oregon, United States

Smart Materials and Nondestructive Evaluation for Energy Systems II

21 March 2016 | Las Vegas, Nevada, United States

Smart Sensor Phenomena, Technology, Networks, and Systems Integration VIII

9 March 2015 | San Diego, California, United States

Smart Materials and Nondestructive Evaluation for Energy Systems

9 March 2015 | San Diego, California, United States

Smart Sensor Phenomena, Technology, Networks, and Systems Integration VII

10 March 2014 | San Diego, California, United States

Smart Sensor Phenomena, Technology, Networks, and Systems Integration VI

10 March 2013 | San Diego, California, United States

Smart Sensor Phenomena, Technology, Networks, and Systems Integration V

12 March 2012 | San Diego, California, United States

Nondestructive Characterization for Composite Materials, Aerospace Engineering, Civil Infrastructure, and Homeland Security V

7 March 2011 | San Diego, California, United States

Smart Sensor Phenomena, Technology, Networks, and Systems IV

7 March 2011 | San Diego, California, United States

Nondestructive Characterization for Composite Materials, Aerospace Engineering, Civil Infrastructure, and Homeland Security IV

8 March 2010 | San Diego, California, United States

Smart Sensor Phenomena, Technology, Networks, and Systems III

8 March 2010 | San Diego, California, United States

Nondestructive Characterization for Composite Materials, Aerospace Engineering, Civil Infrastructure, and Homeland Security III

9 March 2009 | San Diego, California, United States

Smart Sensor Phenomena, Technology, Networks, and Systems II

9 March 2009 | San Diego, California, United States

SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring

8 March 2009 | San Diego, United States

Nondestructive Characterization for Composite Materials, Aerospace Engineering, Civil Infrastructure, and Homeland Security II

11 March 2008 | San Diego, California, United States

Smart Sensor Phenomena, Technology, Networks, and Systems

10 March 2008 | San Diego, California, United States

SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring

9 March 2008 | San Diego, United States

Nondestructive Characterization for Composite Materials, Aerospace Engineering, Civil Infrastructure, and Homeland Security

20 March 2007 | San Diego, California, United States

Sensor Systems and Networks: Phenomena, Technology and Applications for NDE and Health Monitoring

19 March 2007 | San Diego, California, United States

SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring

18 March 2007 | San Diego, United States

Aerospace Applications

13 June 2006 | Dayton, Ohio, United States

Advanced Sensor Technologies for NDE and Structural Health Monitoring II

1 March 2006 | San Diego, CA, United States

Testing, Reliability, and Application of Micro- and Nano-Material Systems IV

1 March 2006 | San Diego, CA, United States

Nondestructive Evaluation and Health Monitoring of Aerospace Materials, Composites, and Civil Infrastructure V

28 February 2006 | San Diego, CA, United States

Nonintrusive Inspection, Structures Monitoring, and Smart Systems for Homeland Security

27 February 2006 | San Diego, CA, United States

Nondestructive Evaluation for Health Monitoring and Diagnostics

26 February 2006 | San Diego, United States

Advanced Sensor Technologies for Nondestructive Evaluation and Structural Health Monitoring

9 March 2005 | San Diego, CA, United States

Testing, Reliability, and Application of Micro- and Nano-Material Systems III

9 March 2005 | San Diego, CA, United States

Nondestructive Evaluation and Health Monitoring of Aerospace Materials, Composites, and Civil Infrastructure IV

8 March 2005 | San Diego, CA, United States

Nondestructive Detection and Measurement for Homeland Security III

7 March 2005 | San Diego, CA, United States

Nondestructive Detection and Measurement for Homeland Security II

17 March 2004 | San Diego, CA, United States

Nondestructive Evaluation and Health Monitoring of Aerospace Materials and Composites III

16 March 2004 | San Diego, CA, United States

Testing, Reliability, and Application of Micro-and Nano-Material Systems II

15 March 2004 | San Diego, CA, United States

Nondestructive Detection and Measurement for Homeland Security

4 March 2003 | San Diego, California, United States

Testing, Reliability, and Application of Micro- and Nano-Material Systems

3 March 2003 | San Diego, California, United States

Nondestructive Evaluation and Health Monitoring of Aerospace Materials and Composites

3 March 2003 | San Diego, California, United States

NDE for Health Monitoring and Diagnostics

2 March 2003 | San Diego, United States

Nondestructive Evaluation and Reliability of Micro- and Nanomaterial Systems

18 March 2002 | San Diego, California, United States

NDE For Health Monitoring and Diagnostics

17 March 2002 | San Diego, United States

NDE of Materials and Composites

7 March 2001 | Newport Beach, CA, United States

6th Annual International Symposium on NDE for Health Monitoring and Diagnostics

4 March 2001 | Newport Beach, United States

Nondestructive Evaluation of Aging Materials and Composites IV

8 March 2000 | Newport Beach, CA, United States

Nondestructive Evaluation of Aging Materials and Composites III

3 March 1999 | Newport Beach, CA, United States

Nondestructive Evaluation of Materials and Composites II

31 March 1998 | San Antonio, TX, United States

Nondestructive Evaluation of Materials and Composites

3 December 1996 | Scottsdale, AZ, United States

Showing 5 of 49 Conference Committees

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