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Articles 1 - 30 of 84
Full-Text Articles in Nuclear Engineering
Prototyping Pinhole Collimators For Imaging Irradiated Nuclear Fuel, Narrie Loftus, Ashish Avachat, Joseph T. Graham, Ryan Fronk, Jordan Fox, Rachel Shaffer, Seth Kilby
Prototyping Pinhole Collimators For Imaging Irradiated Nuclear Fuel, Narrie Loftus, Ashish Avachat, Joseph T. Graham, Ryan Fronk, Jordan Fox, Rachel Shaffer, Seth Kilby
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
Collimator design and fabrication is a costly and time-consuming process that does not lend itself to simplified testing. This manuscript presents an approach for the rapid prototyping of sub-millimeter pinhole collimators for nuclear fuel applications using low-melting-point, high-mass-density materials. Multiple collimators were fabricated to test collimator parameters and properties, including acceptance angle, aperture diameter, and magnification. The fabricated collimators were paired with a position-sensitive CdZnTe detector to determine the detector response convolved with the collimator. Preliminary analysis using these collimators showed that they were effective in collimating multi-energy gamma laboratory sources. Radiography was performed to confirm magnification and determine coarse …
Radiological Safety Assessment Of Gamma Spectroscopy Based Spent Fuel Burnup Analysis At The Itu Triga Mark Ii Reactor, T. Akyurek, Z. Boduroglu, A. Kaya, O. Erbay, I. A. Reyhancan, M. S. Kiziltas, S. Ozcan
Radiological Safety Assessment Of Gamma Spectroscopy Based Spent Fuel Burnup Analysis At The Itu Triga Mark Ii Reactor, T. Akyurek, Z. Boduroglu, A. Kaya, O. Erbay, I. A. Reyhancan, M. S. Kiziltas, S. Ozcan
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
This study investigates radiological safety and photon attenuation behavior during spent fuel inspection and burnup analysis at the ITU TRIGA Mark II Research Reactor. A lead-shielded fuel inspection system equipped with an HPGe detector was used to perform remote gamma spectroscopy on spent fuel elements, ensuring operator safety. Dose rate measurements were taken using a handheld radiation monitor at both the surface and at a distance of 1 m from the inspection system for each fuel element. The highest contact dose rate was observed for the B4 element (6.68 ± 0.60 μSv/h), while the lowest was for F30 (2.4 ± …
Higher-Order Statistical Analysis Of Inter-Arrival Times For Radiation Detector Deadtime Characterization And Paralysis Factor Determination, Abdallah Wazzan, Shoaib Usman, Tayfun Akyurek
Higher-Order Statistical Analysis Of Inter-Arrival Times For Radiation Detector Deadtime Characterization And Paralysis Factor Determination, Abdallah Wazzan, Shoaib Usman, Tayfun Akyurek
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
All real detectors exhibit hybrid behavior that combines both paralyzable and non-paralyzable which requires improved characterization techniques. This study investigates the relationship between detector deadtime parameters and higher-order statistical for inter-arrival time distributions to develop advanced detector characterization. Two comprehensive Monte Carlo simulation approaches were employed using MATLAB: a full radioactive decay curve analysis spanning approximately 4.5 half-lives of Cobalt-60 and Vanadium-52 sources, and a fixed count rate analysis covering practically achievable laboratory conditions (440 to 1,000,000 counts per second). The hybrid deadtime model was implemented with deadtimes ranging from 2.5 to 50 μs for the full simulation and from …
Physics-Informed Machine Learning-Aided Framework For Entrainment Fraction In Gas-Liquid Two-Phase Annular Flow, Anadi Mondal, Subash L. Sharma
Physics-Informed Machine Learning-Aided Framework For Entrainment Fraction In Gas-Liquid Two-Phase Annular Flow, Anadi Mondal, Subash L. Sharma
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
The liquid film flow rate or droplet flow rate in annular flow is determined by a parameter known as the entrainment fraction. Conventional empirical correlations are commonly employed for predicting the entrainment fraction; however, their applicability is often restricted to specific operating conditions and working fluids. Recently, a few machine learning (ML) models have been developed to achieve better accuracy in entrainment fraction prediction. However, these models are completely data-driven, meaning they are good for prediction in the interpolated domain, but exhibit limited generalization capability in the extrapolated domain. To address this limitation, a physics-informed machine learning-aided framework (PIMLAF), combining …
Use Of Gamma-Ray Spectroscopy In Thickness Gauging Of A Complex-Shaped Lead Shield, Joseph T. Graham, Brian Durtschi, Ashish Avachat, Seth Kilby
Use Of Gamma-Ray Spectroscopy In Thickness Gauging Of A Complex-Shaped Lead Shield, Joseph T. Graham, Brian Durtschi, Ashish Avachat, Seth Kilby
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
Methods for measuring the thickness of lead shielding based on 60Co gamma-ray spectroscopy are presented. In applications where a shield's thickness is multiple mean free paths and the shield has a complex shape (i.e. cannot be approximated as a simple solid such as a slab, sphere, semi-infinite medium, etc.), the necessary buildup factors are not available. Thus, determination of shield thickness by means of the Beer–Lambert law requires separating the counts from uncollided photons from the scattered photon contribution. It is demonstrated how the 1332 keV gamma ray of 60Co can be used to precisely quantify lead thicknesses …
Modeling And Characterizing The Electron Backscatter In A Cylindrical Anode-Based Distributed X-Ray Source, Jordan Fox, Seth Kilby, Hyoung Koo Lee, Ayodeji Alajo, Ashish Avachat
Modeling And Characterizing The Electron Backscatter In A Cylindrical Anode-Based Distributed X-Ray Source, Jordan Fox, Seth Kilby, Hyoung Koo Lee, Ayodeji Alajo, Ashish Avachat
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
Upcoming advancements in computed tomography architectures warrants the investigation of new X-ray source designs and the impacts that electron backscatter can have on these designs. One such design being investigated is a distributed, cylindrical anode-based X-ray source. For such a distributed X-ray source, we developed a modeling pipeline for simulating electron optics and transport to characterize the quality of the primary X-ray beam and the electron backscatter behavior. We report our results on the energy distributions of the bremsstrahlung spectra; electron backscatter ratio; and spatial, temporal, and energy distributions of backscattered electrons that return to the anode.
Nondestructive Burnup Evaluation And Gamma Spectroscopy Analysis Of Spent Fuel Elements In The Itu Triga Mark Ii Research Reactor, A. Kaya, O. Erbay, Z. Boduroglu, I. A. Reyhancan, M. S. Kiziltas, T. Akyurek
Nondestructive Burnup Evaluation And Gamma Spectroscopy Analysis Of Spent Fuel Elements In The Itu Triga Mark Ii Research Reactor, A. Kaya, O. Erbay, Z. Boduroglu, I. A. Reyhancan, M. S. Kiziltas, T. Akyurek
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
This study presents a comprehensive burnup analysis of all fuel elements in the ITU TRIGA Mark II research reactor core using non-destructive assay (NDA) techniques based on gamma spectroscopy. Two distinct fuel inspection systems were employed to measure the gamma activity, with137Cs used as the primary burnup indicator due to its strong correlation with fuel depletion. The results show a clear burnup pattern, with higher values in the inner core rings that gradually decreases toward the outer rings. This asymmetric burnup distribution underscores the need for reactor core reconfiguration, for which an optimized layout is proposed. Additionally, gamma …
Full Core Fuel Burnup Assessment Of The Itu Triga Mark Ii Research Reactor Using Gamma Spectroscopy, Z. Boduroglu, A. Kaya, O. Erbay, I. A. Reyhancan, M. S. Kiziltas, T. Akyurek
Full Core Fuel Burnup Assessment Of The Itu Triga Mark Ii Research Reactor Using Gamma Spectroscopy, Z. Boduroglu, A. Kaya, O. Erbay, I. A. Reyhancan, M. S. Kiziltas, T. Akyurek
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
This study investigates the burnup distribution of fuel elements in the ITU TRIGA Mark II research reactor core through gamma spectroscopy using137Cs as a burnup indicator. Non-Destructive Assay (NDA) techniques were employed to analyze fuel depletion, utilizing a specialized fuel investigation system installed above the reactor pool. The results indicate that the highest burnup values, exceeding 5 %, were concentrated in the inner core rings (B and C) due to intense neutron flux exposure, while the outer rings (D, E, F) exhibited lower burnup levels. To address this asymmetric distribution, a proposed fuel reshuffling strategy was analyzed, aiming …
Evaluation Of Two-Group Iate Coupling With Pbe For Beyond Bubbly Flows In A Large Diameter Pipe, Sungje Hong, Joshua P. Schlegel, Subash L. Sharma
Evaluation Of Two-Group Iate Coupling With Pbe For Beyond Bubbly Flows In A Large Diameter Pipe, Sungje Hong, Joshua P. Schlegel, Subash L. Sharma
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
This study evaluates the two-group interfacial area transport equation (2G IATE) coupled with the S-Gamma (Sγ) population balance equation (PBE) model for beyond bubbly flow regimes in a vertical large-diameter pipe. The 2G IATE framework incorporates intergroup mass transfer mechanisms and is implemented within the Sγ model, which assumes a log-normal bubble size distribution. The numerical approach is validated against experimental data from Schlegel et al. (2012), with a focus on the void fraction and interfacial area concentration (IAC) distributions. The results show that 2G IATE improves the predictions of the void fraction and IAC, although its accuracy varies with …
Experimental Investigation Of Subcritical Neutron And Gamma Noise Methods At The Seven Percent Critical Experiment (7upcx), Cole Kostelac, Jesson Hutchinson, George Mckenzie, Robert Weldon, Nicholas Whitman, Ayodeji Babatunde Alajo
Experimental Investigation Of Subcritical Neutron And Gamma Noise Methods At The Seven Percent Critical Experiment (7upcx), Cole Kostelac, Jesson Hutchinson, George Mckenzie, Robert Weldon, Nicholas Whitman, Ayodeji Babatunde Alajo
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
As part of a collaborative international effort organized by Lawrence Livermore National Laboratory (LLNL), with key participants from L'Institut de radioprotection et de s ˆuret´e nucl´eaire (IRSN), Los Alamos National Laboratory (LANL), and Sandia National Laboratories (SNL), a series of high-multiplication subcritical neutron and gamma noise measurements were planned and executed. The primary aim of this research was to advance detector technology, assess the validity of gamma noise for subcriticality measurements, and nuclear criticality safety, focusing on collecting list-mode or time-series data from various reactor configurations with multiplication values ranging from 20 to 310. This comprehensive dataset enabled a detailed …
Impact Of Bubble-Induced Turbulence On Two-Phase Flow Dynamics At High Void Fraction In A Large Diameter Channel, Sungje Hong, Joshua P. Schlegel, Subash L. Sharma
Impact Of Bubble-Induced Turbulence On Two-Phase Flow Dynamics At High Void Fraction In A Large Diameter Channel, Sungje Hong, Joshua P. Schlegel, Subash L. Sharma
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
This study represents the first investigation into the influence of bubble-induced turbulence (BIT) on interfacial area transport mechanisms in gas–liquid two-phase flows under conditions of high void fraction and high velocity in a large diameter channel. Given the unique characteristics of bubble flow in larger channels, the turbulent effects induced by bubbles differ from those observed in smaller channels. However, limited research exists regarding the impact of BIT beyond bubbly flows in large-diameter channels. To address this gap, two approaches for implementing the BIT model are explored: a direct method and an indirect method. This paper assesses both the general …
Flow Regime-Independent Two-Group Interfacial Area Concentration Model For Dispersed Gas-Liquid Flows In Large-Diameter Pipes, Hossein Barati, Takashi Hibiki, Joshua P. Schlegel, Naofumi Tsukamoto
Flow Regime-Independent Two-Group Interfacial Area Concentration Model For Dispersed Gas-Liquid Flows In Large-Diameter Pipes, Hossein Barati, Takashi Hibiki, Joshua P. Schlegel, Naofumi Tsukamoto
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
In many power plants, boiling can result in two-phase flows during normal and accident conditions. Heat and mass transfers through the gas-liquid interface in a two-phase flow process are proportional to the interfacial area concentration (IAC). These calculations for nuclear systems are typically performed using advanced system analysis codes such as TRACE. TRACE uses a two-group (2G) model, where bubbles are divided into two groups according to their drag coefficients. Correlations are used to calculate the group-wise void fractions (VFs) and IACs. This study evaluates the accuracy of the TRACE 2G VF and IAC models for vertically upward dispersed flows …
Implementation Of Tritium Transport In A Gas-Liquid Contactor Cfd Simulation Of Tritium Extraction From Lead-Lithium In Ansys Fluent, Anthony G. Bowers, Subash L. Sharma, Thomas F. Fuerst
Implementation Of Tritium Transport In A Gas-Liquid Contactor Cfd Simulation Of Tritium Extraction From Lead-Lithium In Ansys Fluent, Anthony G. Bowers, Subash L. Sharma, Thomas F. Fuerst
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
Modifications to the Computational Fluid Dynamic (CFD) software ANSYS Fluent were done to quantify and characterize tritium transport in gas-liquid contactors (GLCs). A double-slit, Ergun-like equation was employed for the porous media model, with Ergun coefficients validated with Sulzer's Sulcol software. Tritium transport from PbLi within the GLC was verified against analytical models. The geometry of the CFD model was based on the MELODIE GLC experiment. The hydrodynamic CFD pressure drop results align well with Sulcol estimations and fall between the predictions of the analytical Delft-Olujić and Billet and Schultes models. In terms of mass transfer efficiency, traditional mass transfer …
Synthesis Of Nickel Nanoparticles By Gamma Irradiation And Femtosecond Laser Ablation, V. M. Rao, Y. Han, H. Tsai, C. H.C. Giraldo, T. Akyurek
Synthesis Of Nickel Nanoparticles By Gamma Irradiation And Femtosecond Laser Ablation, V. M. Rao, Y. Han, H. Tsai, C. H.C. Giraldo, T. Akyurek
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
Nickel nanoparticles were synthesized by (i) gamma irradiation of aqueous nickel chloride precursors and (ii) double scan femtosecond laser (FSL) ablation of a pure nickel foil in water. The nanoparticles produced by FSL ablation were further stabilized in acetone. Gamma radiolysis yielded nickel nanoparticles in the 2–22 nm range, with the average particle diameter governed by the total absorbed dose. Nickel nanoparticles produced by double scan FSL ablation were in the 2–17 nm range but less monodispersed than the nanoparticles produced via gamma radiolysis. FSL ablation proved to be superior in terms of yielding a higher number of smaller nanoparticles …
Ai-Driven Uncertainty Quantification & Multi-Physics Approach To Evaluate Cladding Materials In A Microreactor, Alexander Foutch, Kazuma Kobayashi, Ayodeji Babatunde Alajo, Dinesh Kumar, Syed Bahauddin Alam
Ai-Driven Uncertainty Quantification & Multi-Physics Approach To Evaluate Cladding Materials In A Microreactor, Alexander Foutch, Kazuma Kobayashi, Ayodeji Babatunde Alajo, Dinesh Kumar, Syed Bahauddin Alam
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
The pursuit of enhanced nuclear safety has spurred the development of accident-tolerant cladding (ATC) materials for light water reactors (LWRs). This study investigates the potential of repurposing these ATCs in advanced reactor designs, aiming to expedite material development and reduce costs. The research employs a multi-physics approach, encompassing neutronics, heat transfer, thermodynamics, and structural mechanics, to evaluate four candidate materials (Haynes 230, Zircaloy-4, FeCrAl, and SiC–SiC) within the context of a high-temperature, sodium-cooled microreactor, exemplified by the Kilopower design. While neutronic simulations revealed negligible power profile variations among the materials, finite element analyses highlighted the superior thermal stability of SiC–SiC …
Digital Twin-Centered Hybrid Data-Driven Multi-Stage Deep Learning Framework For Enhanced Nuclear Reactor Power Prediction, James Daniell, Kazuma Kobayashi, Ayodeji Alajo, Syed Bahauddin Alam
Digital Twin-Centered Hybrid Data-Driven Multi-Stage Deep Learning Framework For Enhanced Nuclear Reactor Power Prediction, James Daniell, Kazuma Kobayashi, Ayodeji Alajo, Syed Bahauddin Alam
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
The accurate and efficient modeling of nuclear reactor transients is crucial for ensuring safe and optimal reactor operation. Traditional physics-based models, while valuable, can be computationally intensive and may not fully capture the complexities of real-world reactor behavior. This paper introduces a novel hybrid digital twin-focused multi-stage deep learning framework that addresses these limitations, offering a faster and more robust solution for predicting the final steady-state power of reactor transients. By leveraging a combination of feed-forward neural networks with both classification and regression stages, and training on a unique dataset that integrates real-world measurements of reactor power and controls state …
Impact Of Surface And Physical Property On Multiphase Flow In Sealed Vessel: Liquid Dropdown Performance, Mehedi Hasan Tusar, Palash K. Bhowmik, Kazuma Kobayashi, Syed Bahauddin Alam, Shoaib Usman
Impact Of Surface And Physical Property On Multiphase Flow In Sealed Vessel: Liquid Dropdown Performance, Mehedi Hasan Tusar, Palash K. Bhowmik, Kazuma Kobayashi, Syed Bahauddin Alam, Shoaib Usman
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
This study explores multi-phase (i.e., liquid-gas) and multi-fluid (i.e., air-water, and water-silicone oil) flow-pattern and flow-blockage physics phenomena for wall wettability conditions ranging from superhydrophilic to superhydrophobic cases in sealed vessels utilizing computational fluid dynamics (CFD) simulation tools and volume-of-fluid (VOF) method with sharp interface modeling. Detailed modeling and simulation (M&S) of such physics phenomena—in which liquid (e.g., water) stands over top of gas (e.g., air or steam) in a closed channel and exhibited flow blockage, flow reversal related challenges—are pivotal for design, analysis, and qualification of component-level (e.g., heat pipes, heat exchangers) to system-level (e.g., emergency core cooling systems …
Transfer Learning With Spinally Shared Layers, H. M.Dipu Kabir, Subrota Kumar Mondal, Syed Bahauddin Alam, U. Rajendra Acharya
Transfer Learning With Spinally Shared Layers, H. M.Dipu Kabir, Subrota Kumar Mondal, Syed Bahauddin Alam, U. Rajendra Acharya
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
Transfer-learned models have achieved promising performance in numerous fields. However, high-performing transfer-learned models contain a large number of parameters. In this paper, we propose a transfer learning approach with parameter reduction and potential high performance. Although the high performance depends on the nature of the dataset, we ensure the parameter reduction. In the proposed SpinalNet shared parameters, all intermediate-split-incoming parameters except the first-intermediate-split contain a shared value. Therefore, the SpinalNet shared parameters network contains three parameter groups: (1) first input-split to intermediate-split parameters, (2) shared intermediate-split-incoming parameters, and (3) intermediate-split-to-output-split parameters. The total number of parameters becomes lower than the …
Meteorological Data Mining And Synthesis For Supplementing On-Site Data For Regulatory Compliance, Ben Sonpon, Shoaib Usman, Joseph Smith, Sarah Kovaleski, Jason Wibbenmeyer
Meteorological Data Mining And Synthesis For Supplementing On-Site Data For Regulatory Compliance, Ben Sonpon, Shoaib Usman, Joseph Smith, Sarah Kovaleski, Jason Wibbenmeyer
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
Many regulatory requirements add significant delay in the licensing of new nuclear power stations. One area of particular interest is the environmental impact of potential atmospheric release. The purpose of this research is to demonstrate effectiveness of meteorological data mining and synthesis from offsite locations to reduce need for onsite data, hence allowing rapid licensing. The automated procedures tested for data mining and extraction of meteorological data from multiple offsite sources and the data analytic tool developed for data fusion are presented here. Three important meteorological parameters from regulatory compliance are considered for this analysis: wind velocity, wind direction, and …
Meteorological Data Mining And Synthesis For Supplementing On-Site Data For Regulatory Compliance, Ben Sonpon, Shoaib Usman, Joseph Smith, Sarah Kovaleski, Jason Wibbenmeyer
Meteorological Data Mining And Synthesis For Supplementing On-Site Data For Regulatory Compliance, Ben Sonpon, Shoaib Usman, Joseph Smith, Sarah Kovaleski, Jason Wibbenmeyer
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
Many regulatory requirements add significant delay in the licensing of new nuclear power stations. One area of particular interest is the environmental impact of potential atmospheric release. the purpose of this research is to demonstrate effectiveness of meteorological data mining and synthesis from offsite locations to reduce need for onsite data, hence allowing rapid licensing. the automated procedures tested for data mining and extraction of meteorological data from multiple offsite sources and the data analytic tool developed for data fusion are presented here. Three important meteorological parameters from regulatory compliance are considered for this analysis: wind velocity, wind direction, and …
Valorization Of Spent Zn-C Battery And Construction And Demolition Waste (Cdw): Fabrication And Characterization Of Geopolymer Composites For Radiation Shielding Applications, Raul Florez, Carlos H. Castano Giraldo, Sandra M. Restrepo-Arcila, Henry A. Colorado
Valorization Of Spent Zn-C Battery And Construction And Demolition Waste (Cdw): Fabrication And Characterization Of Geopolymer Composites For Radiation Shielding Applications, Raul Florez, Carlos H. Castano Giraldo, Sandra M. Restrepo-Arcila, Henry A. Colorado
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
There is a Serious Threat of Pollution Due to the High Waste of Energy and Materials Worldwide that Needs to Be Decreased. One Way is to Reduce Waste or Use Them in Secondary Processes. New Eco-Friendly Geopolymer Binders Were Fabricated using Metakaolin, CDW, and Battery Waste (BW) Powders as Starting Materials and a Mixture of Potassium Silicate and Sodium Hydroxide as Activation Solutions. 5 Formulations with BW Powder Replacements Ranging from 5 to 40 Wt% Were Prepared and Subjected to Heat Curing at 80 °C for 24 H. the Effect of Zn-C Battery Waste Content on the Phase Composition, Densification, …
Two-Group Drift-Flux Model For Dispersed Gas-Liquid Flow In Large-Diameter Pipes, Hossein Barati, Takashi Hibiki, Joshua P. Schlegel, Naofumi Tsukamoto
Two-Group Drift-Flux Model For Dispersed Gas-Liquid Flow In Large-Diameter Pipes, Hossein Barati, Takashi Hibiki, Joshua P. Schlegel, Naofumi Tsukamoto
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
Interfacial Heat and Mass Transfer Are Prevalent in Industrial Processes. the Interfacial Transfer Rate Can Be Obtained by the Product of their Fluxes and Interfacial Area Concentration (IAC) Calculated by the Interfacial Area Transport Equation (IATE). Bubbles Show Different Behavior According to their Sizes. Hence, Bubbles Are Classified into Two Groups. Consequently, Two-Group IATE is Required Causing to Use of Two Gas Momentum Equations Leading to More Complexity. the Present Study Suggests a New Reliable Two-Group Drift-Flux Modeling to Reduce the Two Gas Momentum Equations to One Gas Mixture Momentum Equation for Gas-Liquid Flow in Large-Diameter Pipes. the Model is …
Cement-Based Materials With Solid-Gel Phase Change Materials For Improving Energy Efficiency Of Building Envelope, Zhuo Liu, Jiang Du, Ryan Steere, Joshua P. Schlegel, Kamal Khayat, Weina Meng
Cement-Based Materials With Solid-Gel Phase Change Materials For Improving Energy Efficiency Of Building Envelope, Zhuo Liu, Jiang Du, Ryan Steere, Joshua P. Schlegel, Kamal Khayat, Weina Meng
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
This paper evaluated the cement-based materials incorporated with novel solid-gel phase change materials (PCMs) for improving the energy efficiency of building envelopes. This novel PCM is form-stable, which will not leak as solid-liquid PCMs do and not need encapsulation, and it features high energy-storage capacity. Experimental results showed that the thermal properties of cement-based materials were improved as the increase of PCM content. A 30% replacement of sand by volume with PCM can increase the latent heat of the mixture from around 0 to 7 J/g and decrease the thermal conductivity of PCM mortar based on the generalized self-consistent (GSC) …
3d Cfd Simulation Of A Bubble Column With Internals: Validation Of Interfacial Forces And Internal Effects For Local Gas Holdup Predictions, Hayder Al-Naseri, J. P. Schlegel, Muthanna H. Al-Dahhan
3d Cfd Simulation Of A Bubble Column With Internals: Validation Of Interfacial Forces And Internal Effects For Local Gas Holdup Predictions, Hayder Al-Naseri, J. P. Schlegel, Muthanna H. Al-Dahhan
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
CFD models (turbulent models and interfacial forces) incorporated with the population balance model (PBM) have been validated, azimuthally, with the gamma-ray-computed tomography (CT) results to address the effect of the presence of internals with different arrangements and diameters. the superficial gas velocity applied was varied from 0.05 to 0.45 m/s. the results exhibit the capability to predict the hydrodynamics of the bubble column, further incorporating the population balance model and promoting the prediction of simulation in high superficial gas velocity. the effect of internals revealed that the gas holdup was significantly enhanced in the bubble column's wall region, while the …
Defect Generation Mechanisms In Silica Under Intense Electronic Excitation By Ion Beams Below 100 K: Interplay Between Radiative Emissions, M. L. Crespillo, Joseph T. Graham, W. J. Weber, F. Agulló-López
Defect Generation Mechanisms In Silica Under Intense Electronic Excitation By Ion Beams Below 100 K: Interplay Between Radiative Emissions, M. L. Crespillo, Joseph T. Graham, W. J. Weber, F. Agulló-López
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
Ion-beam effects on bulk silica at low temperature have been studied with the aim of understanding the routes and mechanisms leading from the initial generation of free carriers and self-trapped excitons (STEs) to the production of two stable defect structures in irradiated silica, non-bridging oxygen hole centers (NBOHCs) and oxygen deficient centers (ODCs). Ion beam induced luminescence (ionoluminescence, IL) spectra were obtained using 3 MeV H, 3.5 MeV He, 19 MeV Si, and 19 MeV Cl ions and a range of cryogenic irradiation temperatures from 30 to 100 K. The kinetic behavior of three emission bands centered at 1.9 eV …
Numerical Study Of Turbulent Flow And Heat Transfer In A Novel Design Of Serpentine Channel Coupled With D-Shaped Jaggedness Using Hybrid Nanofluid, Raditun E. Ratul, Farid Ahmed, Syed B. Alam, Md Rezwanul Karim, Arafat A. Bhuiyan
Numerical Study Of Turbulent Flow And Heat Transfer In A Novel Design Of Serpentine Channel Coupled With D-Shaped Jaggedness Using Hybrid Nanofluid, Raditun E. Ratul, Farid Ahmed, Syed B. Alam, Md Rezwanul Karim, Arafat A. Bhuiyan
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
This Study Aimed to Examine Numerically the Effects of a Dimpled Surface over a Mini-Channel Heat Exchanger on the Flow Characteristics and Heat Transfer Across a Serpentine Channel with a Uniform Rectangular Cross-Section. the Dimples Were Arranged in Parallel with a Spanwise (Y/d) Distance of 3.125 and Streamwise (X/d) Distance of 11.25 Along Just One Side of the Serpentine Channel's Surface. Turbulent Flow Regime with Reynolds Number Ranging from 5 X 103 to 20 X 103 in the Channel with the Surface Modification Was Studied using Water and Various Volume Concentrations (Φ = 0.1%, 0.33%, 0.75%, 1%) of Al2O3-Cu/water Hybrid …
Thermal Analysis Of Si-Igbt Based Power Electronic Modules In 50kw Traction Inverter Application, Mohammad Shahjalal, Tamanna Shams, Sadat Bin Hossain, Md Rishad Ahmed, Mominul Ahsan, Julfikar Haider, Rajib Goswami, Syed B. Alam, Atif Iqbal
Thermal Analysis Of Si-Igbt Based Power Electronic Modules In 50kw Traction Inverter Application, Mohammad Shahjalal, Tamanna Shams, Sadat Bin Hossain, Md Rishad Ahmed, Mominul Ahsan, Julfikar Haider, Rajib Goswami, Syed B. Alam, Atif Iqbal
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
Estimation of Accurate IGBT Junction Temperature is Crucial for Reliability Assessment. the Well-Known RC Lumped Approach Can Help Predict Junction Temperature. However, This Method Suffers from Inaccuracy While Characterizing the Thermal Behavior of Several IGBT Modules Mounted to the Liquid-Cooled Heatsink. Specifically, the Thermal Challenge Originates from the Thermal Cross-Coupling and Module-To-Module Heat Spreading and the Converter Cooling Condition. This Article Demonstrates a Methodology to Study the Impact of Heat Spreading, Thermal Interface Material, and Massive Size Liquid Cold-Plate on the overall Thermal Behavior. a Case Study of 50 KW Traction Inverter is Chosen to Demonstrate the Benefit of Early …
3d Cfd Simulation Of A Bubble Column With Internals: Validation Of Interfacial Forces And Internal Effects For Local Gas Holdup Predictions, Hayder Al-Naseri, Joshua P. Schlegel, Muthanna H. Al-Dahhan
3d Cfd Simulation Of A Bubble Column With Internals: Validation Of Interfacial Forces And Internal Effects For Local Gas Holdup Predictions, Hayder Al-Naseri, Joshua P. Schlegel, Muthanna H. Al-Dahhan
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
CFD Models (Turbulent Models and Interfacial Forces) Incorporated with the Population Balance Model (PBM) Have Been Validated, Azimuthally, with the Gamma-Ray-Computed Tomography (CT) Results to Address the Effect of the Presence of Internals with Different Arrangements and Diameters. the Superficial Gas Velocity Applied Was Varied from 0.05 to 0.45 M/s. the Results Exhibit the Capability to Predict the Hydrodynamics of the Bubble Column, Further Incorporating the Population Balance Model and Promoting the Prediction of Simulation in High Superficial Gas Velocity. the Effect of Internals Revealed that the Gas Holdup Was Significantly Enhanced in the Bubble Column's Wall Region, While the …
Small Modular Reactors, Joshua P. Schlegel, P. K. Bhowmik
Small Modular Reactors, Joshua P. Schlegel, P. K. Bhowmik
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
Small Modular Reactors (SMRs) have been a very promising development in nuclear power over the last two decades. SMRs are defined as nuclear reactors with a power output of less than 300MWe. This is in comparison to gigawatt-size reactors, which can have electrical output of 1000–1500MWe or more. This chapter will consist of two major sections. the first will be a detailed summary of the small modular reactor designs being proposed around the world. This section will focus on those that are the furthest along in their development but will also include some information about the wide variety of proposed …
Reinforcement Of The Plasmon–Phonon Coupling In Α-Quartz Via Deposition Of Gold Nanoparticles In Etched Ion Tracks, Maria C. Garcia Toro, Miguel L. Crespillo, Jose Olivares, Joseph T. Graham
Reinforcement Of The Plasmon–Phonon Coupling In Α-Quartz Via Deposition Of Gold Nanoparticles In Etched Ion Tracks, Maria C. Garcia Toro, Miguel L. Crespillo, Jose Olivares, Joseph T. Graham
Nuclear Engineering and Radiation Science Faculty Research & Creative Works
This study reports a large reinforcement of the plasmon–phonon coupling in alpha quartz achieved through the controlled deposition of gold nanoparticles into nano templates produced through chemical etching of ion tracks. Preferential agglomeration of nanoparticles within the etched ion tracks (nano wells) was observed in Scanning Electron Microscopy and Atomic Force Microscopy images. Raman characterization of quartz substrates with different nanoparticle concentrations revealed a relationship between the plasmon–phonon coupling intensity and nanoparticle concentration. Reinforcement of the plasmon–phonon coupling was observed as an increase in the Raman intensity with increasing concentration of deposited nanoparticles. The intensity initially increased linearly with nanoparticle …