Engineering Commons^™

Non-Destructive Infrared Thermographic Curing Analysis Of Polymer Composites, Md Ashiqur Rahman, Javier Becerril, Dipannita Ghosh, Nazmul Islam, Ali Ashraf

Mechanical Engineering Faculty Publications and Presentations

Infrared (IR) thermography is a non-contact method of measuring temperature that analyzes the infrared radiation emitted by an object. Properties of polymer composites are heavily influenced by the filler material, filler size, and filler dispersion, and thus thermographic analysis can be a useful tool to determine the curing and filler dispersion. In this study, we investigated the curing mechanisms of polymer composites at the microscale by capturing real-time temperature using an IR Thermal Camera. Silicone polymers with fillers of Graphene, Graphite powder, Graphite flake, and Molybdenum disulfide (MoS₂) were subsequently poured into a customized 3D printed mold for …

Non-Destructive Material Analysis Of Metals And Composites Via Thermography, Jonathan R. Doubt, James L. Chapman

Materials Engineering

The Naval Surface Warfare Center, Port Hueneme Division, is interested in the development of non-destructive damage assessment of shipboard materials via drones at distance. Long Pulsed Thermography (LPT), a method of non-destructive evaluation, was investigated as a possible method for detecting damage in metals (5005h24 Al alloy and 1008 carbon steel) and composites (aramid fiber honeycomb sandwich structure) at distances from 0.5 m to 3.0 m. LPT was conducted using two 1000 W can lights to heat the samples, and a FLIR E8-XT thermal camera. The images were then analyzed using ImageJ software to determine if damage could be detected …

Composite Compression Co-Moulding: A Warpage Reduction Investigation, David Knezevic

Electronic Thesis and Dissertation Repository

To accommodate the increasing need for vehicle emission reduction, automotive manufacturers are presently looking at the next generation of lightweight materials. Glass fibre-reinforced thermoplastic composites belong to this group and exhibit mechanical properties that resemble traditional metals but at a reduced weight and with improvements on other characteristics. Unfortunately, they are affected by processing-related warpage, especially when fabricated by means of the Long Fibre-reinforced Thermoplastics – Direct (LFT-D) manufacturing process, a technology that is valuable because of its high throughput and flow lengths. This occurs for many reasons but reinforcing LFT-D with Glass Mat Thermoplastics (GMT) – another material format …

Synthesis Of Sodium Ammonium Hydrophosphate And Sodium Dihydrophosphate Based On Extraction Phosphoric Acid From Central Kyzylkum Phosphorites, Kamola Arifdjanova, Kholtura Mirzakulov, Sherzod Khujamberdiev, Melikulova Gavkhar

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the research is the synthesis of sodium ammonium hydrogen phosphate and sodium dihydrogen phosphate based on purified extraction phosphoric acid.

The acid was purified from accompanying impurities by precipitation methods using sodium carbonate and metasilicate, washed burnt phosphoconcentrate, barium carbonate, acid neutralization with gaseous ammonia. Pre-neutralization of the purified solution of monoammonium phosphate with sodium carbonate to the ratio Na₂O:P₂O₅ = 0.44 and subsequent drying at a temperature of 50 °С allows to obtain sodium ammonium hydrogen phosphate tetrahydrate, and at 100 °С sodium dihydrogen phosphate monohydrate.

The individuality and purity of …

The Impact Of Precipitation On State Of The Slopes Surface And Thermal Activity Of The Mine Waste Dump – Preliminary Study, Zenon Różański, Paweł Wrona, Grzegorz Pach, Adam Niewiadomski, Tomasz Suponik, Robert Frączek, Leszek Balcarczyk

Journal of Sustainable Mining

Precipitation, especially with a high intensity, affects the condition of mining waste dumps. The article presents the results of research aimed at determining the impact of rain on water erosion on the slopes of a coal waste dump and its thermal state. Preliminary tests of the condition of two slopes of the coal waste dump in Libiąż (Poland) undertaken in the frameworks of the TEXMIN project was carried out using modern geodesy techniques (low-ceiling photogrammetry and TLS terrestrial laser scanning). The current geometry of the slope surface was faithfully reproduced in the form of a cloud of points with known …

Development Of In-Situ Radiometric Inspection Methods For Quality Assurance In Laser Powder Bed Fusion, Cody S. Lough

Doctoral Dissertations

“Laser Powder Bed Fusion (LPBF) metal Additive Manufacturing (AM) fabricates 3D metal parts layer-by-layer. The process enables production of geometrically complex parts that are difficult to inspect with traditional methods. The LPBF parts experience significant geometry driven thermal variations during manufacturing. This creates microstructure and mechanical property inhomogeneities and can stochastically cause defects. Mission critical applications require part qualification by measuring the defects non-destructively. The layer-to-layer nature of LPBF permits non-intrusive measurement of radiometric signals for a part’s entire volume. These measurements provide thermal features that correlate with the local part health. This research establishes Optical Emission Spectroscopy (OES) and …

Spectral Absorption Coefficient Of Additive Manufacturing Materials, Nicholas J. Wallace, Matthew R. Jones, Nathan B. Crane

Faculty Publications

Active thermography techniques are of interest for quality assurance of additive manufacturing processes. However, accurate measurements of thermophysical properties of materials are required to successfully implement active thermography. In particular, the spectral absorption coefficient of materials commonly used in additive manufacturing must be known to accurately predict the spatial distribution of thermal energy generated from absorption of power emitted by a laser or pulsed flash lamp. Accurate measurements of these optical properties are also needed to develop greater understanding of additive manufacturing processes that rely on radiative heat transfer to fuse powders. This paper presents spectral absorption coefficient measurements and …

Early Detection Of Near-Surface Void Defects In Concrete Pavement Using Drone Based Thermography And Gpr Methods, Zhigang Shen, Ece Erdogmus, George Morcous, Chngsheng Cheng, Zhexiong Shang, Theresa Mccabe, Antony Mohsen Kamal Masoud Kodsy

Nebraska Department of Transportation: Research Reports

The goal of this research is to evaluate the feasibility and the performance of using UAV-mounted infrared thermography (IRT) and ground penetration radar (GPR) to detect sub-surface voids caused by consolidation issues in concrete pavement. The motivation of the study is to identify the consolidation defects as early as the initial set of concrete to avoid having this problem in large pavement sections, which is costly and time consuming to repair. Using the two technologies in combination to detect subsurface voids in the concrete initial set stage is new and aims to take advantage of the strengths and minimize the …

Multi-Physics-Based Approach To Active Microwave Thermography, Seyed Ali Mirala

Doctoral Dissertations

“The goal of this work is to advance a novel nondestructive testing (NDT) method for controlled, rapid, and effective inspection of a structure through the integration of microwave NDT and thermography, referred to as Active Microwave Thermography (AMT). In AMT, the structure under test is exposed to microwave radiation and the thermal profile of the structure is monitored via a thermal camera in order to obtain desired information regarding the structure. This new technique is applicable across a wide range of NDT needs including detection of voids, delamination, water ingress, debonding, and cracks in numerous structures such as carbon fiber …

Bridge Deck Delamination Segmentation Based On Aerial Thermography Through Regularized Grayscale Morphological Reconstruction And Gradient Statistics, Chongsheng Cheng, Zhexiong Shang, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

Environmental and surface texture-induced temperature variation across the bridge deck is a major source of errors in delamination detection through thermography. This type of external noise poises a significant challenge for conventional quantitative methods such as global thresholding and k-means clustering. An iterative top-down approach is proposed for delamination segmentation based on grayscale morphological reconstruction. A weight-decay function was used to regularize the reconstruction for regional maxima extraction. The mean and coefficient of variation of temperature gradient estimated from delamination boundaries were used for discrimination. The proposed approach was tested on a lab experiment and an in-service bridge deck. The …

Examination Of Flow Dynamics And Passive Cooling In An Ultra Compact Combustor, Tylor C. Rathsack

Theses and Dissertations

The Ultra Compact Combustor (UCC) promises to greatly reduce the size of a gas turbine engine’s combustor by altering the manner in which fuel is burnt. Differing from the common axial flow combustor, the UCC utilizes a rotating flow, coaxial to the engine’s primary axis, in an outboard circumferential cavity as the primary combustion zone. The present study investigates two key UCC facets required to further this combustor design. The first area of investigation is cooling of the Hybrid Guide Vane (HGV). This UCC specific hardware acts as a combustor center body that alters the exit flow angle and acts …

Cubesat Active Thermal Management In Support Of Cooled Electro-Optical Instrumentation For Advanced Atmospheric Observing Missions, Lucas Anderson, Charles Swenson, Ryan Davidson, Arthur J. Mastropietro, Elham Maghsoudi, S. Luong, Stefano Cappucci, I. Mckinley

Electrical and Computer Engineering Faculty Publications

The need for advanced cooled electro-optical instrumentation in remote observations of the atmosphere is well known and demonstrated by SABER on the TIMED mission. The relatively new use of small satellites in remote earth observing missions as, well as the challenges, are epitomized by the upcoming NOAA EON-IR 12U CubeSat missions. These advanced CubeSat missions, which hope to accomplish scientific objectives on the same scale as larger more traditional satellites, require advanced miniaturized cryocoolers and active methods for thermal management and power control. The active CryoCubeSat project (ACCS) is a demonstration of such a technology. Utilizing Ultrasonic Additive Manufacturing (UAM) …

Schlieren Visualization Of Shaping Air During Operation Of An Electrostatic Rotary Bell Sprayer: Impact Of Shaping Air On Droplet Atomization And Transport, Adnan Darwish Ahmad, Ahmad M. Abubaker, Ahmad A. Salaimeh, Nelson K. Akafuah

Institute of Research for Technology Development Faculty Publications

Electrostatic rotary bell sprayers (ERBSs) are widely used in the automotive industry. In ERBS, atomization is facilitated using centrifugal forces which disintegrate the paint film inside the cup into droplets at the cup edge. The droplets are then transported by the flow of a shaping air (SA) and electrostatic forces to a target surface; the characteristics of these droplets dramatically influence the quality of a painted surface and the painting transfer efficiency. In the current paper, a novel Schlieren-based visualization of the shaping air in the absence of paint droplets was performed during a qualitative investigation to delineate shaping air …

Qualitative Evaluation Of Cfrp-Concrete Bond Using Non-Destructive And Destructive Testing Methods, Ankita Anil Lad

Civil Engineering Theses

CFRP (Carbon Fiber Reinforced Polymer) laminates have been used as externally bonded reinforcements for retrofitting and structural strengthening of concrete structures. The adequacy of the CFRP bonding highly depends on the bond integrity between the concrete and CFRP laminates. Considering the reliability of this bonding technique, premature debonding of laminates from the concrete substrate is a major concern. The bond performance may be influenced directly by various parameters; some of the parameters like surface wetness, surface preparation, presence of voids in concrete substrate and overhead versus on the top installation of CFRP laminate have been discussed in this study. During …

Fatigue Crack Detection Using Unmanned Aerial Systems In Under-Bridge Inspection, Sattar Dorafshan, Marc Maguire, Nathan V. Hoffer, Calvin Coopmans

Civil and Environmental Engineering Faculty Publications

The applications of Unmanned Aerial Systems (UAS) for bridge inspection, with emphasis on under-bridge inspection and fatigue crack detection, were studied in this report. The potential benefits and challenges of using UAS for bridge inspection were identified through an extensive literature survey. The feasibility of using UAS for fatigue crack detection was studied by determining the minimum lighting, camera distance and environmental requirements for three UAS. The DJI Mavic UAS performed better than the others in both indoor and outdoor GPS-denied inspections. An in-service bridge in Ashton, Idaho was inspected using this UAS to find fatigue cracks. No fatigue crack, …

Tumor Detection And Treatment By Means Of Thermography And Laser Irradiation, Euiheon Chung, Gyungseok Oh, Su Woong Yoo

Advances in Optics for Biotechnology, Medicine and Surgery XV

While passive thermal imaging of temperature difference between tumor and neighboring tissue provides limited contrast, active thermography with external thermal modulation may provide higher contrast presumably due to the distinct thermal response from the tumor tissue. We have investigated physiologically relevant parameters such as response rate with respect to thermal modulation and relaxation time. This new imaging modality in the infrared regime may prove useful as a label-free and non-invasive screening tool. On the other hand, we propose a novel use of controlled thermal injury from non-ablative fractional laser irradiation for early treatment of tumor growth with a fiber-based thulium …

Development Of Active Microwave Thermography For Structural Health Monitoring, Ali Foudazi

Doctoral Dissertations

"Active Microwave Thermography (AMT) is an integrated nondestructive testing and evaluation (NDT&E) method that incorporates aspects of microwave NDT and thermography techniques. AMT uses a microwave excitation to generate heat and the surface thermal profile of the material or structure under test is subsequently measured using a thermal camera (or IR camera). Utilizing a microwave heat excitation provides advantages over traditional thermal excitations (heat lamps, etc.) including the potential for non-contact, selective and focused heating. During an AMT inspection, two heating mechanisms are possible, referred to as dielectric and induction heating. Dielectric heating occurs as a result of the interaction …

Phase Sensitive Thermography Of Magnetostrictive Materials Under Periodic Excitations, Peng Yang

Theses and Dissertations

The use of giant magnetostrictive materials in actuator and sensor applications is still relatively new. Giant magnetostrictive materials, such as Terfenol-D, are unique in producing large deformation under a magnetic field. Applications of these materials in solid state actuators and transducers may require more knowledge on the interaction between geometry and material properties for a specific design. In order to gain more understanding of the magnetostriction mechanism, phase sensitive or lock-in thermography has been used to study Terfenol-D. Thermography is useful in that it allows for full field measurement of the surface of an object with a relatively simple setup. …

Interference-Free Gas-Phase Thermometry At Elevated Pressure Using Hybrid Femtosecond/Picosecond Rotational Coherent Anti- Stokes Raman Scattering, Joseph D. Miller, Chloe Elizabeth Dedic, Sukesh Roy, James R. Gord, Terrence R. Meyer

Terrence R Meyer

Rotational-level-dependent dephasing rates and nonresonant background can lead to significant uncertainties in coherent anti-Stokes Raman scattering (CARS) thermometry under high-pressure, lowtemperature conditions if the gas composition is unknown. Hybrid femtosecond/picosecond rotational CARS is employed to minimize or eliminate the influence of collisions and nonresonant background for accurate, frequency-domain thermometry at elevated pressure. The ability to ignore these interferences and achieve thermometric errors of <5% is demonstrated for N2 and O2 at pressures up to 15 atm. Beyond 15 atm, the effects of collisions cannot be ignored but can be minimized using a short probe delay (~6.5 ps) after Raman excitation, …

Examination Of Heat Flux Through A Surface Using Digital Image Processing Of Infrared Images, Nicholas D. True

Honors Theses

The task for this project was to design and construct a system that could be used to examine heat transfer through a surface by analyzing images produced using thermal imaging cameras. A long rectangular box made of pinewood was constructed and a light bulb was inserted to provide a heating element. The front face of the box was made to be interchangeable so that various materials could be tested. Two Flir I5 thermal imaging cameras were used to take pictures of both sides of the front face at specific time intervals in order to determine the temperature distribution of the …

Determination Of Optimal Experimental Parameters For Transient Thermography Imaging Using Finite-Element Models, Tsuchin Chu, Ajay Mahajan, A. Digrgorio, S. Russell

Dr. Ajay Mahajan

A study was conducted to determine the optimal inspection parameters such as range and time for finding defects in carbon/epoxy composite panels using IR thermography imaging. The present paper presents an innovative method for automatically selecting these parameters for evaluating composites based on a series of finite-element models. Such finite-element models of composite panels with flaws at different depth locations were constructed a priori and analysed to estimate the optimal operating parameters. The optimal inspection range and time were identified in the contour plots obtained from the appropriate finite-element analysis results. A graphite–epoxy composite panel with phantom defects at various …

Degradation And Fatigue Involving Dissipated Processes, Md Liakat Ali

LSU Doctoral Dissertations

Irreversible material degradation due to cyclic mechanical loading is investigated utilizing the concept of thermodynamic entropy, plastic strain energy, and temperature slope measurement. Uniaxial tension-compression and fully-reversed bending fatigue tests are performed over a wide range of loading conditions with metallic and composite materials subject to both constant- and variable-amplitude loading. A methodology is developed for the estimation of the fatigue fracture entropy (FFE) and fatigue toughness of metallic specimens in a rapid fashion. It is found that the FFE and the fatigue toughness of each material tested are within a small band. The value of FFE is found to …

Integration Of Microwave And Thermographic Ndt Methods For Corrosion Detection, Dustin F. Pieper, Kristen M. Donnell, Mohammad Tayeb Ahmad Ghasr, Edward C. Kinzel

Electrical and Computer Engineering Faculty Research & Creative Works

Infrastructure health monitoring is an important issue in the transportation industry. For the case of cement-based structures in particular, detection of corrosion on reinforcing steel bars (rebar) is an ongoing problem for aging infrastructure. There have been a number of techniques that have shown promise in this area including microwave nondestructive testing (NDT) and thermography. Thermography is quite advantageous as it is an established method, and can be utilized for large inspection areas with intuitive results. Typical heat sources include induction heating and flash lamps, but these are not without drawbacks. Microwave nondestructive testing has also been successful at detecting …

A Thermographic Method For Remaining Fatigue Life Prediction Of Welded Joints, Paul Thomas Williams

LSU Master's Theses

A non-destructive thermographic technique is adapted and applied to study the fatigue life and behavior of welded specimens made from two different materials. Results show good agreement between experimental predictions of consumed fatigue life and predicted fatigue life. Further, the thermal evolution of the specimens is used to calculate Damage Parameter, which is also used to make fatigue life predictions with promising results. To gain further insight Buckingham Pi theorem is also applied to determine the role of the important parameters involved in a dimensionless form. For this purpose, a series of experiments were performed and used for the analysis …

An Experimental Investigation Of Corrosion Fatigue Life Via Thermographic Method, Richard Wayne Purvis

LSU Master's Theses

The effect of prior corrosion fatigue damage on the thermographic response of 1018 low carbon steel is investigated. Specimens were subject to rotating bending fatigue at 38 Hz loading frequency while being exposed to a 3.5% NaCl and distilled water solution. Some specimens were subject to corrosion fatigue for part of their fatigue life and then their thermographic response measured under fatigue in air at 62 Hz loading frequency. Fatigue tests in air with thermographic measurement were performed as a comparison. It was observed that the initial temperature rise after corrosion fatigue fits the previously proposed model for air fatigue, …

Thermal Defect Analysis On Distribution Transformer Using A Rlc Network And Thermography, Geoffrey O. Asiegbu, Ahmed M. A Haidar, Kamarul Hawari

Faculty of Engineering and Information Sciences - Papers: Part A

Electrical transformers are vital components found virtually in most power-operated equipments. These transformers spontaneously radiate heat in both operation and steady-state mode. Should this thermal radiation inherent in transformers rises above allowable threshold a reduction in efficiency of operation occurs. In addition, this could cause other components in the system to malfunction. The aim of this work is to detect the remote causes of this undesirable thermal rise in transformers such as oil distribution transformers and ways to control this prevailing thermal problem. Oil transformers consist of these components: windings usually made of copper or aluminum conductor, the core normally …

Document Flash Thermography, Cory A. Larsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents the application of ash thermography techniques to the analysis of documents. The motivation for this research is to develop the ability to non-destructively reveal covered writings in archaeological artifacts such as the Codex Selden or Egyptian car- tonnage. Current common signal processing techniques are evaluated for their effectiveness in enhancing subsurface writings found within a set of test documents. These processing techniques include: false colorization, contrast stretching, histogram equalization, median altering, Gaussian low-pass altering, layered signal reconstruction and thermal signal reconstruction (TSR), several contrast image definitions, differential absolute contrast (DAC), correlated contrast, derivative images, principal component thermography …

Principal Component Analysis Based Image Fusion Routine With Application To Stamping Split Detection, Yi Zhou

All Dissertations

This dissertation presents a novel thermal and visible image fusion system with application in online automotive stamping split detection. The thermal vision system scans temperature maps of high reflective steel panels to locate abnormal temperature readings indicative of high local wrinkling pressure that causes metal splitting. The visible vision system offsets the blurring effect of thermal vision system caused by heat diffusion across the surface through conduction and heat losses to the surroundings through convection. The fusion of thermal and visible images combines two separate physical channels and provides more informative result image than the original ones.
Principal Component Analysis …

Automation Of Non-Destructive Testing Techiniques Used For Finding Defects, Bhanu Singh

All Theses

This master thesis focuses on the automation and fusion of non-destructive testing methods. The research includes the fusion of non-destructive testing methods done with infrared micro-bolometer and ultrasonic transducers. A control system which utilized mechanical, electrical, electronic systems and computer aided technologies was developed. Conveyor belt system, PLC (programmable logic controller), XYZ mechanism and different sensors were utilized to automate the process of capturing images and a communication link was set up between thermal camera and system that controls the ultrasonic testing apparatus, to integrate the two techniques. The test results from the thermal camera were utilized in ultrasonic testing. …

Induction Assisted Thermography For Inspection Of Micro Defects On Sheet Metals, Sree Pamidi

All Theses

The work focuses on Induction assisted Thermography as a non-contact and non-destructive method of Inspecting micro defects on sheet metals used for making automotive body panels. Induction heating as a source of excitation to elevate the temperatures of sheet metals for uniform heating and detect ability of the defect is the main objective of the study.
Experiments are done on sheet metal samples with defects using excitation techniques like Pulse and Electromagnetic Induction. The thermal images obtained from the infrared camera are used to quantitatively analyze the detect ability of defects on sheet metals. The limitations of using Pulse technique …