This document summarizes Andrew Oles' PhD dissertation on modeling of solar particle receivers for hydrogen production and thermochemical energy storage. It describes particle receivers as a potential next-generation concentrating solar power technology with solid particles as the heat transfer medium. The document outlines the modeling of inert and reactive particle receivers, including simulations of prototype and commercial-scale receivers to analyze performance tradeoffs. Selective absorption in particles is investigated, showing higher efficiencies are possible by tuning infrared emissivity.
Accelerators and Applications- Summer Training in Physics 16Kamalakkannan K
Particle accelerators are used to study nuclear structure by providing high energies needed to see subatomic details. They work by using electric fields to accelerate charged particles, gaining kinetic energy. Accelerators are essential for understanding materials through techniques like Rutherford backscattering spectroscopy (RBS) which uses ion beams and detection of backscattered ions to determine thickness, composition, and depth profiling of materials. Key applications of accelerators include ion implantation to dope materials, cancer treatment, materials characterization using techniques like RBS, and transmuting nuclear waste.
Performance prediction of PV & PV/T systems using Artificial Neural Networks ...Ali Al-Waeli
This presentation offers insight into use of ANN and machine learning for various applications in solar energy. Prepared and presented by Dr. Ali H. A. Alwaeli.
2017 ECS San Francisco Section Cubicciotti Award Ceremony TalkTianyu Liu
Invited by the Electrochemical Society San Francisco Section to give the presentation to highlight my research and extracurricular activities. The award ceremony was held on the campus of UC Berkeley.
The Materials Project and computational materials discoveryAnubhav Jain
1. The Materials Project aims to accelerate materials discovery through high-throughput computational screening of materials properties using density functional theory calculations.
2. Over 60,000 compounds have been computed so far, with properties including total energies, optimized structures, band structures, and elastic tensors.
3. The goal is to compute properties for over 90,000 materials to help researchers discover new materials for applications like batteries, thermoelectrics, and other energy technologies.
Tianyu Liu's dissertation focused on exploring carbonaceous materials for supercapacitors. Key contributions included developing hierarchical porous carbons from chitosan with high surface area for energy storage, manufacturing graphene aerogel electrodes with direct ink writing for thick porous structures, and stabilizing conducting polymers through carbonaceous coatings to improve cycling stability. The work aimed to enhance capacitance, rate capability, and cycling life through rational material design and synthesis.
IRJET- Dual Band Cylindrical DRA with Carbon Nano TubeIRJET Journal
This document summarizes research on a dual-band cylindrical dielectric resonator antenna (DRA) using carbon nanotubes (CNTs). Key points:
- The antenna is designed to operate in both L and S bands using the fundamental TE11 mode and higher-order TE13 mode of the cylindrical DRA.
- CNTs are used to miniaturize the antenna structure due to their high permittivity. Simulation and experimental results show reasonable agreement on return loss, radiation pattern, and gain.
- The paper reviews properties of CNTs that make them suitable for antenna applications, such as conductivity, permittivity, and impact on resonance frequency. Modeling tools are discussed for designing C
20180320 polymer based nanomaterials for supercapacitorsTianyu Liu
The slides for a guest lecture of a graduate course (Chem 6564) offered by the Department of Chemistry, Virginia Polytechnic Institute and State University.
Accelerators and Applications- Summer Training in Physics 16Kamalakkannan K
Particle accelerators are used to study nuclear structure by providing high energies needed to see subatomic details. They work by using electric fields to accelerate charged particles, gaining kinetic energy. Accelerators are essential for understanding materials through techniques like Rutherford backscattering spectroscopy (RBS) which uses ion beams and detection of backscattered ions to determine thickness, composition, and depth profiling of materials. Key applications of accelerators include ion implantation to dope materials, cancer treatment, materials characterization using techniques like RBS, and transmuting nuclear waste.
Performance prediction of PV & PV/T systems using Artificial Neural Networks ...Ali Al-Waeli
This presentation offers insight into use of ANN and machine learning for various applications in solar energy. Prepared and presented by Dr. Ali H. A. Alwaeli.
2017 ECS San Francisco Section Cubicciotti Award Ceremony TalkTianyu Liu
Invited by the Electrochemical Society San Francisco Section to give the presentation to highlight my research and extracurricular activities. The award ceremony was held on the campus of UC Berkeley.
The Materials Project and computational materials discoveryAnubhav Jain
1. The Materials Project aims to accelerate materials discovery through high-throughput computational screening of materials properties using density functional theory calculations.
2. Over 60,000 compounds have been computed so far, with properties including total energies, optimized structures, band structures, and elastic tensors.
3. The goal is to compute properties for over 90,000 materials to help researchers discover new materials for applications like batteries, thermoelectrics, and other energy technologies.
Tianyu Liu's dissertation focused on exploring carbonaceous materials for supercapacitors. Key contributions included developing hierarchical porous carbons from chitosan with high surface area for energy storage, manufacturing graphene aerogel electrodes with direct ink writing for thick porous structures, and stabilizing conducting polymers through carbonaceous coatings to improve cycling stability. The work aimed to enhance capacitance, rate capability, and cycling life through rational material design and synthesis.
IRJET- Dual Band Cylindrical DRA with Carbon Nano TubeIRJET Journal
This document summarizes research on a dual-band cylindrical dielectric resonator antenna (DRA) using carbon nanotubes (CNTs). Key points:
- The antenna is designed to operate in both L and S bands using the fundamental TE11 mode and higher-order TE13 mode of the cylindrical DRA.
- CNTs are used to miniaturize the antenna structure due to their high permittivity. Simulation and experimental results show reasonable agreement on return loss, radiation pattern, and gain.
- The paper reviews properties of CNTs that make them suitable for antenna applications, such as conductivity, permittivity, and impact on resonance frequency. Modeling tools are discussed for designing C
20180320 polymer based nanomaterials for supercapacitorsTianyu Liu
The slides for a guest lecture of a graduate course (Chem 6564) offered by the Department of Chemistry, Virginia Polytechnic Institute and State University.
Testing of photovoltaic system performance
Prepared by:
Dr. Ali H. A. Al-Waeli
Postdoctoral researcher
Solar Energy Research Institute (SERI)
National University of Malaysia (UKM)
Some of the figures/tables in this presentation are not owned by the
Presenter, they are material copyrighted to their rightful owners. This presentation is intended for non-profit educational purposes.
Slides with copyrighted material (images/tables) contain the letter C in the bottom left corner.
The actual presentation contains elements that are not mentioned in the PowerPoint and even edits to the PowerPoint. Only a portion of the PowerPoint is provided. Still, this presentation contain useful information and figures with regards to performance measurements of photovoltaic modules.
This presentation was prepared independently by the presenter and is owned by:
Dr. Ali H. A. Alwaeli
This document discusses ion implantation, which involves accelerating ions into a solid material to modify its properties. It describes the basic ion implantation process and components. SRIM and TRIM software are introduced for simulating ion implantation, allowing calculation of ion range, energy loss mechanisms, and damage within materials. Key outputs from the simulations include ion range profiles, damage distributions, and recoil energies. The document provides examples of simulation results for various ion species and implant conditions in materials like silicon carbide.
Space Radiation Superconductive Shield (SR2S) is an EU funded FP7 project which is researching new technology to protect astronauts in space from radiation. On 9th April 2014 in Torino, Italy, SR2S held their first conference to give an update on the project so far.
For more information visit:
www.sr2s.eu
Twitter - @SR2SMars
This document discusses applications and future work regarding nanoantennas. Some potential applications include integrating nanoantennas into consumer electronics to continuously charge batteries, coating buildings to supplement the power grid, and fabricating them into polyester fabric. Future work includes designing nanoantennas to operate at other wavelengths to concurrently collect visible, near-infrared, and mid-infrared energy. Researchers also aim to develop photonic systems and switches that can efficiently handle the absorbed light without converting it to electricity.
Kartik Goyal presented his dissertation on the design and optimization of optical Yagi-Uda nantennas for beam steering applications. He discussed the need for optical nantennas in applications such as communication, photovoltaics, and medical imaging. Through his research, he analyzed different nantenna designs, materials, and substrates. His final optimized design was a 9-element circular loop optical Yagi-Uda nantenna made of gold with a gallium arsenide substrate that achieved high directivity for beam steering.
This document presents research on the feasibility of using radioisotope-based electron sources for space applications. It introduces two new types of space propulsion systems: the Minaka thruster and Kabila thruster. The Minaka thruster uses clusters of self-powered radioisotope cells to generate micro-newtons of thrust. It applies the principle of self-sufficiency to power the radioisotope electron sources. The Kabila thruster uses a hollow cathode with a radioisotope heat source instead of a conventional heater. It was found to save up to 3% in overall power compared to conventional ion thrusters. Both systems aim to overcome the energetic limitations of traditional space propulsion through novel use of radioisotopes
This document discusses the use of superconductive magnetic shielding for radiation protection on exploration missions. It describes the radiation risks faced during long-duration space travel and proposes active magnetic shielding as a solution. Magnetic shield configurations like toroidal and solenoidal fields are examined, with previous modeling showing a racetrack toroid could provide effective shielding against galactic cosmic rays if its magnetic field strength and radius products reach approximately 15 Tm. Mechanical and structural design challenges for magnet systems in space are also addressed.
Gold nanorods have potential for photothermal cancer therapy. When exposed to laser light near their surface plasmon resonance wavelengths, gold nanorods efficiently absorb light and generate heat through electron oscillations. Smaller nanorods absorb shorter wavelengths. Nanorods have transverse and longitudinal surface plasmon resonances depending on their aspect ratio. Their strong light absorption and efficient conversion to heat makes them suitable for using mild hyperthermia to selectively destroy tumors through plasmonic photothermal therapy.
The document discusses direct conversion as an alternative to photovoltaics for space solar power. It summarizes two potential near-term and long-term direct conversion concepts - solar pumped masers in the near-term and shocked photonic crystals in the long-term. Calculations are provided for the expected mass per unit power and efficiency of these concepts, which could enable applications like space solar power satellites and electric propulsion with higher efficiency and lower mass than current technologies.
Kilohertz-Rate MeV Ultrafast Electron Diffraction for Time-resolved Materials...Yi Lin
Ultrafast electron diffraction (UED) enables direct insight into structural dynamics of solids. Relativistic MeV-scale electron beams yield access to high-momentum scattering and preserve beam coherence, yet their application at high repetition rates for high-sensitivity UED has been limited. We discuss the High Repetition-rate Electron Scattering (HiRES) instrument at Berkeley Lab and its first applications to UED of metallic films and quantum materials. HiRES employs a state-of-the-art photoinjector with RF bunch compression to generate high-brightness, relativistic 0.75 MeV electron pulses with up to 105-106 el./pulse and with highest achievable coherence length of 10 nm. The resulting high momentum range (±10 Å-1) yields access over multiple Brillouin zones. The sub-500 fs electron pulses are provided at 0.1-250 kHz repetition rate, and combined with optical pumping via a 1.03 µm fiber amplifier enable UED of cryogenically cooled materials. We will show examples of first experiments including transient Debye-Waller dynamics in ultrathin metals at kHz repetition rate as well as studies of charge density waves in 2D materials.
Work at LBNL was supported by the DOE Office of Basic Energy Sciences.
Simulation of AlGaN/Si and InN/Si ELECTRIC –DEVICESijrap
In this work, efficient solar-blind metal-semiconductor photodetectors grown on Si (111) by
molecular beam epitaxy are reported. Growth details are described,the comparison enters the
properties electric of InN/Si and AlGaN/Si photodectors with 0.2 μm of AlGaN and InN layers.
Modeling and simulation were performed by using ATLAS-TCAD simulator. Energy band
diagram, doping profile, conduction current density,I-V caracteristic , internal potential and
electric field were performed.
The document discusses Angle-Resolved Photoemission Spectroscopy (ARPES), an experimental technique used to study the electronic structure of materials. ARPES works based on the photoelectric effect, measuring the kinetic energy and emission angle of photoelectrons ejected from a material exposed to X-ray or UV light. By measuring how photoelectron intensity varies with kinetic energy and angle, ARPES can directly probe a material's band structure, providing information on electron energy and momentum. The document outlines the principles and techniques of ARPES, explaining how it is used to map out full band structures and study phenomena like Dirac nodes in graphene.
Fresnel lenses concentrate sunlight to high temperatures and are a promising alternative energy technology for Nigeria's energy problems. Experiments showed Fresnel lenses achieved stagnation temperatures up to 1300°C, significantly higher than reflective concentrators which reached only 200-300°C. Fresnel lenses had thermal efficiencies over 85% and figures of merit over 0.6, indicating they are well-suited for thermal and electric energy generation in tropical climates like Nigeria. Future work will further explore using Fresnel lenses for thermal and photovoltaic energy harvesting to help address Nigeria's energy needs in a sustainable way.
1) The document describes a Monte Carlo model developed to simulate exciton diffusion in organic solar cells containing different porphyrin compounds.
2) The model simulated the diffusion and decay of excitons in a cube representing the solar cell material. Results showed less aggregation of PCBM molecules and longer exciton lifetimes for the compound TCO4PP compared to TCM4PP.
3) By varying the simulation parameters, the model determined TCO4PP had significantly longer exciton diffusion lengths than TCM4PP, indicating it could enable up to two times higher efficiencies in organic solar cells.
1) External irradiation from a broadband solid-state plasma light source was introduced to a laminar ethylene-air diffusion flame.
2) Soot samples extracted from different heights above the burner showed increases in soot volume fraction, primary particle diameter, and radius of gyration with external irradiation.
3) The dominant soot formation mechanism was found to transform from nucleation and coalescence to surface growth and agglomeration between heights of 20-30mm above the burner when external irradiation was applied.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Research Poster Hu, Davis SULI Summer 2014Davis Hu
This document summarizes research into reducing graphene oxide (GO) using lasers for applications in thin-film supercapacitors. The goal was to determine the optimized laser conditions for GO reduction. GO was deposited on glass slides in increasing layers and reduced using lasers at different wavelengths, powers, and through different microscope objectives. Raman spectroscopy and impedance measurements showed that a 633nm laser most effectively reduced GO over time, as evidenced by a decreasing ID/IG intensity ratio. The maximum capacitance of GO and reduced GO were measured through cyclic voltammetry and electrochemical impedance spectroscopy. The research demonstrated that lasers can effectively reduce GO for applications in flexible electronics and energy storage.
The document discusses creating a titanium dioxide (TiO2) thin film photocatalyst to be used in solar cells. TiO2 nanoparticles are deposited onto a substrate using a sputtering technique. The film is then analyzed using X-ray photon spectroscopy (XPS) and X-ray diffraction (XRD) to determine its elemental composition and structure. Conductivity tests are also performed to measure how well the film conducts electricity. Potential curriculum enhancements integrating the project include student labs on sol-gel synthesis and demonstrations of solar-powered vehicles.
Biomass energy comes from burning plant and animal matter to produce heat and electricity. Some advantages are that it is renewable and does not rely on limited resources like coal. Possible disadvantages include the costs of collecting waste materials and some air pollution from burning. An experiment showed that bacteria in grass clippings raised the temperature as they broke down the grass, releasing biomass energy in the form of heat. Biomass can be used to produce fuels like biodiesel and questions were provided to check understanding of these concepts.
Este documento resume las características de las principales corrientes económicas desde el mercantilismo hasta el keynesianismo. Describe los principales pensadores, teorías, actividades económicas y la relación con el estado de cada corriente como el mercantilismo, fisiocratismo, clásica, marxista, neoclásica y keynesiana.
El documento describe tres modelos económicos: la economía mixta, la economía de libre comercio y la economía comercializada. La economía mixta implica la participación conjunta del sector público y privado en la economía a nivel micro y macro. La economía de libre comercio permite que individuos y empresas realicen actividades comerciales sin obstáculos. La economía comercializada se refiere al proceso de llevar productos y servicios del productor al consumidor a nivel micro y macro.
Testing of photovoltaic system performance
Prepared by:
Dr. Ali H. A. Al-Waeli
Postdoctoral researcher
Solar Energy Research Institute (SERI)
National University of Malaysia (UKM)
Some of the figures/tables in this presentation are not owned by the
Presenter, they are material copyrighted to their rightful owners. This presentation is intended for non-profit educational purposes.
Slides with copyrighted material (images/tables) contain the letter C in the bottom left corner.
The actual presentation contains elements that are not mentioned in the PowerPoint and even edits to the PowerPoint. Only a portion of the PowerPoint is provided. Still, this presentation contain useful information and figures with regards to performance measurements of photovoltaic modules.
This presentation was prepared independently by the presenter and is owned by:
Dr. Ali H. A. Alwaeli
This document discusses ion implantation, which involves accelerating ions into a solid material to modify its properties. It describes the basic ion implantation process and components. SRIM and TRIM software are introduced for simulating ion implantation, allowing calculation of ion range, energy loss mechanisms, and damage within materials. Key outputs from the simulations include ion range profiles, damage distributions, and recoil energies. The document provides examples of simulation results for various ion species and implant conditions in materials like silicon carbide.
Space Radiation Superconductive Shield (SR2S) is an EU funded FP7 project which is researching new technology to protect astronauts in space from radiation. On 9th April 2014 in Torino, Italy, SR2S held their first conference to give an update on the project so far.
For more information visit:
www.sr2s.eu
Twitter - @SR2SMars
This document discusses applications and future work regarding nanoantennas. Some potential applications include integrating nanoantennas into consumer electronics to continuously charge batteries, coating buildings to supplement the power grid, and fabricating them into polyester fabric. Future work includes designing nanoantennas to operate at other wavelengths to concurrently collect visible, near-infrared, and mid-infrared energy. Researchers also aim to develop photonic systems and switches that can efficiently handle the absorbed light without converting it to electricity.
Kartik Goyal presented his dissertation on the design and optimization of optical Yagi-Uda nantennas for beam steering applications. He discussed the need for optical nantennas in applications such as communication, photovoltaics, and medical imaging. Through his research, he analyzed different nantenna designs, materials, and substrates. His final optimized design was a 9-element circular loop optical Yagi-Uda nantenna made of gold with a gallium arsenide substrate that achieved high directivity for beam steering.
This document presents research on the feasibility of using radioisotope-based electron sources for space applications. It introduces two new types of space propulsion systems: the Minaka thruster and Kabila thruster. The Minaka thruster uses clusters of self-powered radioisotope cells to generate micro-newtons of thrust. It applies the principle of self-sufficiency to power the radioisotope electron sources. The Kabila thruster uses a hollow cathode with a radioisotope heat source instead of a conventional heater. It was found to save up to 3% in overall power compared to conventional ion thrusters. Both systems aim to overcome the energetic limitations of traditional space propulsion through novel use of radioisotopes
This document discusses the use of superconductive magnetic shielding for radiation protection on exploration missions. It describes the radiation risks faced during long-duration space travel and proposes active magnetic shielding as a solution. Magnetic shield configurations like toroidal and solenoidal fields are examined, with previous modeling showing a racetrack toroid could provide effective shielding against galactic cosmic rays if its magnetic field strength and radius products reach approximately 15 Tm. Mechanical and structural design challenges for magnet systems in space are also addressed.
Gold nanorods have potential for photothermal cancer therapy. When exposed to laser light near their surface plasmon resonance wavelengths, gold nanorods efficiently absorb light and generate heat through electron oscillations. Smaller nanorods absorb shorter wavelengths. Nanorods have transverse and longitudinal surface plasmon resonances depending on their aspect ratio. Their strong light absorption and efficient conversion to heat makes them suitable for using mild hyperthermia to selectively destroy tumors through plasmonic photothermal therapy.
The document discusses direct conversion as an alternative to photovoltaics for space solar power. It summarizes two potential near-term and long-term direct conversion concepts - solar pumped masers in the near-term and shocked photonic crystals in the long-term. Calculations are provided for the expected mass per unit power and efficiency of these concepts, which could enable applications like space solar power satellites and electric propulsion with higher efficiency and lower mass than current technologies.
Kilohertz-Rate MeV Ultrafast Electron Diffraction for Time-resolved Materials...Yi Lin
Ultrafast electron diffraction (UED) enables direct insight into structural dynamics of solids. Relativistic MeV-scale electron beams yield access to high-momentum scattering and preserve beam coherence, yet their application at high repetition rates for high-sensitivity UED has been limited. We discuss the High Repetition-rate Electron Scattering (HiRES) instrument at Berkeley Lab and its first applications to UED of metallic films and quantum materials. HiRES employs a state-of-the-art photoinjector with RF bunch compression to generate high-brightness, relativistic 0.75 MeV electron pulses with up to 105-106 el./pulse and with highest achievable coherence length of 10 nm. The resulting high momentum range (±10 Å-1) yields access over multiple Brillouin zones. The sub-500 fs electron pulses are provided at 0.1-250 kHz repetition rate, and combined with optical pumping via a 1.03 µm fiber amplifier enable UED of cryogenically cooled materials. We will show examples of first experiments including transient Debye-Waller dynamics in ultrathin metals at kHz repetition rate as well as studies of charge density waves in 2D materials.
Work at LBNL was supported by the DOE Office of Basic Energy Sciences.
Simulation of AlGaN/Si and InN/Si ELECTRIC –DEVICESijrap
In this work, efficient solar-blind metal-semiconductor photodetectors grown on Si (111) by
molecular beam epitaxy are reported. Growth details are described,the comparison enters the
properties electric of InN/Si and AlGaN/Si photodectors with 0.2 μm of AlGaN and InN layers.
Modeling and simulation were performed by using ATLAS-TCAD simulator. Energy band
diagram, doping profile, conduction current density,I-V caracteristic , internal potential and
electric field were performed.
The document discusses Angle-Resolved Photoemission Spectroscopy (ARPES), an experimental technique used to study the electronic structure of materials. ARPES works based on the photoelectric effect, measuring the kinetic energy and emission angle of photoelectrons ejected from a material exposed to X-ray or UV light. By measuring how photoelectron intensity varies with kinetic energy and angle, ARPES can directly probe a material's band structure, providing information on electron energy and momentum. The document outlines the principles and techniques of ARPES, explaining how it is used to map out full band structures and study phenomena like Dirac nodes in graphene.
Fresnel lenses concentrate sunlight to high temperatures and are a promising alternative energy technology for Nigeria's energy problems. Experiments showed Fresnel lenses achieved stagnation temperatures up to 1300°C, significantly higher than reflective concentrators which reached only 200-300°C. Fresnel lenses had thermal efficiencies over 85% and figures of merit over 0.6, indicating they are well-suited for thermal and electric energy generation in tropical climates like Nigeria. Future work will further explore using Fresnel lenses for thermal and photovoltaic energy harvesting to help address Nigeria's energy needs in a sustainable way.
1) The document describes a Monte Carlo model developed to simulate exciton diffusion in organic solar cells containing different porphyrin compounds.
2) The model simulated the diffusion and decay of excitons in a cube representing the solar cell material. Results showed less aggregation of PCBM molecules and longer exciton lifetimes for the compound TCO4PP compared to TCM4PP.
3) By varying the simulation parameters, the model determined TCO4PP had significantly longer exciton diffusion lengths than TCM4PP, indicating it could enable up to two times higher efficiencies in organic solar cells.
1) External irradiation from a broadband solid-state plasma light source was introduced to a laminar ethylene-air diffusion flame.
2) Soot samples extracted from different heights above the burner showed increases in soot volume fraction, primary particle diameter, and radius of gyration with external irradiation.
3) The dominant soot formation mechanism was found to transform from nucleation and coalescence to surface growth and agglomeration between heights of 20-30mm above the burner when external irradiation was applied.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Research Poster Hu, Davis SULI Summer 2014Davis Hu
This document summarizes research into reducing graphene oxide (GO) using lasers for applications in thin-film supercapacitors. The goal was to determine the optimized laser conditions for GO reduction. GO was deposited on glass slides in increasing layers and reduced using lasers at different wavelengths, powers, and through different microscope objectives. Raman spectroscopy and impedance measurements showed that a 633nm laser most effectively reduced GO over time, as evidenced by a decreasing ID/IG intensity ratio. The maximum capacitance of GO and reduced GO were measured through cyclic voltammetry and electrochemical impedance spectroscopy. The research demonstrated that lasers can effectively reduce GO for applications in flexible electronics and energy storage.
The document discusses creating a titanium dioxide (TiO2) thin film photocatalyst to be used in solar cells. TiO2 nanoparticles are deposited onto a substrate using a sputtering technique. The film is then analyzed using X-ray photon spectroscopy (XPS) and X-ray diffraction (XRD) to determine its elemental composition and structure. Conductivity tests are also performed to measure how well the film conducts electricity. Potential curriculum enhancements integrating the project include student labs on sol-gel synthesis and demonstrations of solar-powered vehicles.
Biomass energy comes from burning plant and animal matter to produce heat and electricity. Some advantages are that it is renewable and does not rely on limited resources like coal. Possible disadvantages include the costs of collecting waste materials and some air pollution from burning. An experiment showed that bacteria in grass clippings raised the temperature as they broke down the grass, releasing biomass energy in the form of heat. Biomass can be used to produce fuels like biodiesel and questions were provided to check understanding of these concepts.
Este documento resume las características de las principales corrientes económicas desde el mercantilismo hasta el keynesianismo. Describe los principales pensadores, teorías, actividades económicas y la relación con el estado de cada corriente como el mercantilismo, fisiocratismo, clásica, marxista, neoclásica y keynesiana.
El documento describe tres modelos económicos: la economía mixta, la economía de libre comercio y la economía comercializada. La economía mixta implica la participación conjunta del sector público y privado en la economía a nivel micro y macro. La economía de libre comercio permite que individuos y empresas realicen actividades comerciales sin obstáculos. La economía comercializada se refiere al proceso de llevar productos y servicios del productor al consumidor a nivel micro y macro.
The document summarizes research on performance analysis of high temperature sensible heat storage systems during charging and discharging cycles. The objectives were to develop a thermal model to predict performance, optimize the storage bed design, and analyze performance of beds made of cast steel and concrete. The results show that charging times were 683 seconds for cast steel and 3650 seconds for concrete, with energy storage of 62.85 MJ and 62.39 MJ respectively. Discharging times and energy recovered were also reported. Exergy efficiency was analyzed. Thermal models were validated and provided insights into heat transfer and temperature variations during the cycles.
El colágeno es la proteína más abundante en el cuerpo humano y es esencial para la elasticidad y firmeza de la piel, huesos y otros tejidos. Se encuentra principalmente en la piel, huesos, cartílagos, músculos y ligamentos. La producción de colágeno disminuye a partir de los 25 años, lo que causa arrugas, dolores articulares y osteoporosis. Es importante obtener colágeno a través de la dieta y suplementos para mantener la salud de la piel y articul
El documento describe los diferentes tipos de accidentes cerebrovasculares hemorrágicos, incluidos los intracerebrales, subaracnoideos y ventriculares. Explica las causas comunes como la hipertensión, traumatismos, aneurismas y uso de fármacos o toxinas. También detalla los signos y síntomas como alteración del estado de conciencia, cefalea, convulsiones y pérdida de visión, y los métodos de diagnóstico como la tomografía computarizada, angiografía y electroencefalograma.
Project for 3º eso students. It deals with NGOs and solidarity. It requires group work and cooperative learning. English should be used in their final presentations.
Energy can be converted between different forms, but is never lost or destroyed. There are several examples of energy conversions, such as electrical energy being converted to light, heat, or kinetic energy through devices like toasters or solar panels. Kinetic energy from motion can also be converted to electrical energy through dynamos on bicycles. Chemical energy from fuels is converted to kinetic energy and heat when cars burn gas in their engines.
thermo chemical energy storage system for solar plantsRajneesh Gautam
Thermochemical energy storage (TES) systems store energy through chemical reactions and have a higher energy density than sensible or latent heat storage. They involve dissociating a chemical into components during charging and reintegrating them during discharge. One example is an ammonia-based TES system for concentrating solar power plants. It uses the reversible dissociation of ammonia (NH3) into nitrogen (N2) and hydrogen (H2) gases. During charging, solar energy dissociates NH3, and the components are stored. During discharge, the gases recombine exothermically to regenerate NH3, releasing energy. Such chemical TES systems could provide baseload power but require more research on performance and costs
There are two main types of radioactivity: natural and induced. Natural radioactivity occurs in nature from unstable nuclei and can occur through alpha, beta, or gamma decay, each resulting in the emission of different particles or energy from the nucleus. Radioactive decay occurs at a predictable rate and can be used to determine the age of materials through calculation of half-lives. Radioisotopes have many uses including medical tracers, pollution detection, cancer treatment, food preservation, and providing nuclear fuel for power plants.
Intro separate hydrogen and oxygen from water through electrolysisrahulchinoy
This document provides instructions for building a home electrolysis system to generate hydrogen and oxygen gases from water. It describes collecting the gases in plastic bottles by running electrolyzed water through the bottles. Electrodes made of braided wire and plastic sheeting are used to separate the hydrogen and oxygen during electrolysis when connected to a 6-12V battery power source. The generated gases can then be supplied to a vehicle engine through the fuel intake to potentially serve as an alternative to gasoline. Safety disclaimers are included as the instructions note the concept has not been built and tested by the author.
Electrolysis is the process of using electricity to split water into hydrogen and oxygen gases. It works by passing an electric current through water, which separates the water into its basic elements. Salty water is used because the salt allows electricity to flow better through the solution during electrolysis.
Cronologia de la Iglesia (I): Epoca Visigoda; Alta y Baja Edad MediaESPAÑA PRECONCILIAR
Cronologia Iglesia española: Historia religiosa ; Historia eclesiastica, benedictinos, carmelitas, cartujos, cistercienses, compostela, santo domingo de guzmán, reconquista, pedro Nolasco, San Felix de mata, Raimundo Peñafort, Raimundo de Fitero, templarios, temple, ordenes militares, Fernando III el santo, Gundisalvo, Escuela de Toledo,
Anatomia, fisiología, etiologia, posición del apendice, manifestaciones clinicas tempranas y tardias, etiopatogenia, examen fisico y signos de apendicitisfisiopatología, etapas de la apendicitis, diagnostico, tratamiento quirurgico, Clasificacion.
Escape 24 biomass power plant with integrated drying-effective utilization of...Tesfaldet Gebregerges
This document describes integrating biomass drying into a biomass power plant to improve efficiency. It analyzes a base case power plant and three drying options: a hot air dryer, a two-stage hot air and steam dryer, and a flue gas dryer. The two-stage dryer using low pressure steam achieved the highest efficiency of 29.92% with a dried biomass feed of 31,576 kg/hr and final moisture content of 4.5%. Integrating drying recovers waste heat and increases the overall plant efficiency compared to the base case.
La digestión implica la degradación de los alimentos en moléculas más pequeñas a través de procesos como la hidrólisis. Estos procesos ocurren principalmente en el intestino delgado y grueso, donde los carbohidratos, lípidos y proteínas son hidrolizados en monosacáridos, ácidos grasos y aminoácidos respectivamente antes de la absorción. La desnutrición y un exceso de alimentos como las grasas pueden causar enfermedades.
The document discusses Applied Hydrogen's conductive hydrogen storage technology for applications in hydrogen fuel storage, air conditioning, and energy storage. It aims to commercialize a solid-state hydrogen storage material integrated into a porous metal support structure ("Hydripak") that provides faster hydrogen absorption/desorption rates compared to powder-bed hydrides due to better heat conductivity. Key target markets include industrial and vehicular hydrogen storage, merchant hydrogen delivery, renewable energy storage, UPS, and freon-free cooling. Applied Hydrogen plans to demonstrate commercial feasibility and develop marketable products over the next 3 years.
20191101 Wang Invited Talk at APTSE (Thermal Energy Harvesting and Conversion)lwang78
This document summarizes research on using nano-engineered materials for high-efficiency solar thermal energy harvesting and conversion. It discusses using metamaterials and metafilms as selective absorbers and emitters to control the spectral properties of materials. Experimental results show the metafilm absorbers maintain high solar absorptance while significantly reducing infrared emittance, even after high-temperature testing. Theoretical analyses predict the metafilm designs can improve the efficiency of solar thermophotovoltaic energy conversion systems from around 10% to over 17% at 50 suns concentration by optimizing the material structures and incorporating a cavity reflector. Current work involves fabricating and testing a solar thermophotovoltaic experimental setup using the metafilm
2023Dec ASU Wang NETR Group Research Focus and Facility Overview.pptxlwang78
The document summarizes the research of Dr. Liping Wang's Nano-Engineered Thermal Radiation Group at Arizona State University. The group focuses on efficient energy harvesting, power conversion, and radiative thermal control using thermophotonic absorption and emission. Key areas of research include selective thermal emission and absorption for solar energy applications, near-field thermal radiation, and tunable thermal emission for applications like radiative cooling. The group has state-of-the-art facilities for optical characterization, thermophotonic energy conversion testing, and measuring near-field radiation.
Optical Absoprtion of Thin Film SemiconductorsEnrico Castro
This document analyzes the optical properties of several thin film semiconductors. It characterizes the transmittance, reflectance, and absorption of CdS films deposited at different times, as well as Sb-S-Se films deposited at different temperatures. Key results include the absorption coefficient, transmission and reflection percentages in different wavelength regions, and estimates of photon flux and potential short circuit current density for each film based on their bandgaps. Optical properties were measured using UV-VIS spectroscopy to understand how effectively the materials could absorb light.
This document discusses a proposed mission concept to send a probe to 1000 AU within 50 years using currently feasible technologies. Key elements include:
1) Using a solar gravity assist at Jupiter to eliminate angular momentum, then falling to within 4 solar radii of the Sun to leverage the high speeds for an escape trajectory.
2) The probe would use a high-Isp propulsion system like solar thermal or nuclear thermal to accelerate during a 15-minute perihelion maneuver for solar system escape.
3) Enabling technologies discussed include high-temperature carbon-carbon shields, efficient radioisotope power, and laser optical communications. Follow-on studies are proposed to further develop the concepts.
DESIGN, OPTIMIZATION AND DEVELOPMENT OF SOLAR THERMAL HEAT RECEIVER SYSTEM WI...Journal For Research
Against a backdrop of our world’s changing climate solar thermal power generation shows great potential to move global energy production away from fossil fuels to non-polluting sources. A parameter study was conducted based on the previous analysis to improve specific aspects of the initial design using a value of benefit analysis to evaluate the different design. This project focused on the design, analysis and verification of a high temperature solar receiver. Computational Fluid Dynamic (CFD) analysis of Radiation model is carried out with new geometry design of receiver. Discrete Transfer Radiation Model (DTRM) model is used for numerical simulation.
This document discusses the design, optimization, and development of a solar thermal heat receiver system with a parabolic concentric collector. A computational fluid dynamics (CFD) analysis was conducted using a discrete transfer radiation model (DTRM) to simulate heat transfer and optimize the receiver design. The CFD analysis found that the receiver design achieved an average temperature of 453K on the receiver wall and outlet temperature of air at 392K with an air mass flow rate of 0.08kg/s. Higher temperatures can be achieved by using materials with higher reflectivity for the reflector and selecting optimal working fluids.
Picosecond Time-Resolved Studies of Exciton Transport in Conjugated Polymer N...Louis C. Groff II, PhD
Dissertation defense talk presented November 2015.
Conjugated polymer nanoparticles (CPNs) are a model system for the study of complex, nanoscale, multichromophoric interactions. Here, we are focused on furthering our understanding of the physical picture, processes, length scales, and time scales of energy transport in conjugated polymers. In particular, we are interested in determining how parameters related to the nanoscale structure and composition of CPs affect energy transport, which is investigated using steady-state and time-resolved fluorescence spectroscopy in conjunction with Monte Carlo simulation methods. Such information could prove useful for optimizing the structure and composition of device layers (e.g., in photovoltaic devices). We additionally seek to develop brighter, red-emitting CPNs through Förster Resonance Energy Transfer (FRET) for their use in biomedical imaging applications. Analysis of dye-doped and polymer blended CPNs shows that the doped CPNs exhibit bright, red-shifted emission, owing to the highly efficient energy transfer from the host polymer PFBT to the respective dopants (the fluorescent dye perylene red in dye-doped CPNs, and the polymer MEH-PPV in blended CPNs). An exciton diffusion energy transfer model was employed to simulate exciton dynamics in doped CPNs, and additionally to determine the intrinsic exciton diffusion length for PFBT in the absence of quenching defects. Solvent-induced swelling methods were utilized to study how swelling affects the multiple energy transfer cascade to intrinsic defects and/or aggregate species in CPNs, which modulates the exciton dynamics and fluorescence properties of CPNs. Changes in the rate of exciton transport over a range of solvent compositions were measured using picosecond
fluorescence anisotropy decay (FAD). Analysis of the results indicates increased fluorescence lifetimes and fluorescence quantum yield with increasing THF concentration. Additionally, the FAD and model results indicate that the rate of exciton transport is significantly increased in the nanoparticle state compared to polymer in good solvent. The results elucidate a tradeoff between exciton transport rates and fluorescence quantum efficiency in conjugated polymer systems, which can be exploited for improvement of organic semiconductor-based devices.
p-i-n Solar Cell Modeling with Graphene as ElectrodeWahiduzzaman Khan
Graphene is a 2-D atomic layer of carbon atoms with unique electronic properties like outstanding carrier mobility, high carrier saturation velocity, excellent thermal conductivity, high mechanical strength, transparency, thinness, and flexibility which make graphene an excellent choice of material for advanced applications in future solar cell design. We modeled a solar cell using graphene as the front electrode to study its performance and compare the performance with that of other possible contenders- indium tin oxide (ITO), widely used material at present and carbon nanotube (CNT), another promising material in this regard. Numerical solutions of the electrostatic and transport equations were obtained using the finite-element method. It was found that solar cell with graphene electrode can outperform the others. We also studied its performance as a function of various parameters. The developed model and obtained results are important for the design of solar cell with graphene as electrode.
This document summarizes a student group's progress defense presentation on their research developing nano-structured transparent contacts for dye sensitized solar cells. The group reports on their goals of analyzing photon absorption characteristics and enhancing efficiency. Their experimental design involves modeling amorphous silicon layers in a solar cell. Simulation results so far are presented. The group's timeline shows further analysis planned through the end of the year, culminating in a final defense. References cited research on TiO2 anodes, organic sensitizers, and carbon nanotube photoanodes to enhance dye sensitized solar cell efficiency.
637131main radiation shielding symposium_r1Clifford Stone
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Горбунов Н.А., Государственная морская академия им. С.О. Макарова, г. Санкт-Петербург
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Microelectronic technologies for alternative energy sourcesMariya Aleksandrova
The document discusses microelectronic technologies for alternative energy sources such as thermoelectric, piezoelectric, and solar cells. It describes how energy harvesting works by capturing ambient energy sources and converting it to usable electric energy using transducers. Key technologies discussed include thin film thermoelectric converters made of bismuth telluride, thin film piezoelectric converters using materials like PZT and ZnO, and thin film solar cells fabricated through processes like e-beam evaporation and sputtering. Applications mentioned include powering devices for remote patient monitoring, machinery monitoring, and personal electronics.
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Dissertation Defense - Final
1. University of Maryland, College Park
Modeling of Solar Particle Receivers for
Hydrogen Production and Thermochemical
Energy Storage
Andrew S. Oles
December 11th, 2014
Committee: Professor Greg Jackson, Chair
Professor Ken Kiger
Professor Amir Riaz
Professor Peter Sunderland
Professor Michael Zachariah
2. University of Maryland, College Park
How Concentrating Solar Works
Electricity
Heliostat
Field
Solar
Receiver
Storage Generation
Hot Storage
Cold
Storage
• Central receiver designs
− High outlet temperatures for efficient
power cycles or chemical processes
− Amenable to high solar concentrations
for cost effective
2
3. University of Maryland, College Park
• Concentrating solar power require new receiver and storage
technologies to meet DOE targets for cost of solar-thermal electricity
(SunShot Initiative)
• Solid particle receivers have potential as next-generation design
– Outlet temperatures > 600 °C for higher-efficiency power-cycles or high-
temperature chemistry (like H2O splitting for renewable H2)
Motivation
3
4. University of Maryland, College Park
Falling Particle Receivers
• Low-stress on solid materials for high
temperature solar absorption
– Low-cost construction
– Extended material life
• Potential for effective energy storage
– High heat capacity
– Stable materials for high-T storage
• Potential as a reactor
– High temperature redox chemistry
– Potential for fuel, chemicals, or even
metals production
Conc. Solar
Radiation
Cold Particle
Flow In
Hot Particle
Flow Out 4
5. University of Maryland, College Park
Thermochemical Fuel Production
• Oxide reduction can be used for thermochemical energy storage or
fuel productions
• Ceria is a common material studied for solar fuel production (Kodama
et al., Haile et al., Steinfeld et al., Abanades et al., Davidson et al.)
Particle
Receiver
5
6. University of Maryland, College Park
• Background
• Inert Particle Receiver Simulations
– Model description
– Prototype-scale results
– Commercial-scale results
• Reactive Particle Receiver Simulations
– Reactive particle modeling
– Ceria particle results
– Perovskite particle results
• Reactive Particle Receiver CFD Simulations
– Reactive particle modeling
– Ceria particle results
– Comparison of simplified and CFD model
Outline
• Background
• Inert Particle Receiver Simulations
– Model description
– Prototype-scale results
– Commercial-scale results
• Reactive Particle Receiver Simulations
– Reactive particle modeling
– Ceria particle results
– Perovskite particle results
• Reactive Particle Receiver CFD Simulations
– Reactive particle modeling
– Ceria particle results
– Comparison of simplified and CFD model
6
7. University of Maryland, College Park
• Inert particle receivers can achieve most SunShot performance
requirements with proper design
– Integrated storage with high-Cp particles
– Low-cost materials stable in air over large temperature range
– Work with next-gen (supercritical Rankine) power cycles with firing
temperatures above 650 ºC
• Challenges in inert particle receiver design
– Difficult to design with complex interaction of radiation-driven heat
transfer and multi-phase particulate flow
– Tradeoffs between receiver “solar-absorption” efficiency ηsolar and
particle outlet temperatures Tp,out needed for high-efficiency power
cycles or high-temperature chemistry.
Inert Particle Receivers
7
8. University of Maryland, College Park
Gas and Particle Dynamics Model
Side View of
Receiver
Sheath Gas
Particle
Curtain
Non-
participant
gas
• Particle momentum solved in Lagrangian
frame
• Solid-gas mass and momentum coupling
• Air entrainment adapted from semi-
empirical approach of Liu[1]
– Gaussian gas-phase velocity profile, uy,g
– Entrainment proportional to mean uy,g
• Empirical particle spreading of curtain
thickness (Δzcurt) based on Kim et al.[2]
[1]: Liu, Z. (2003). University of Wollongong Thesis Collections.
[2] Kim, K., et al. (2009). Sol. Energy. 83, 1784-1793.
g
ρ
ρρ
d
uu
CC
ρ
ρ
dt
du
p
gp
p
2
gy,py,
SD
p
gpy,
4
3
uz,g,entrained
=auy,g
8
9. University of Maryland, College Park
Heat-Transfer Model
• Particle curtain transport adapted from the
approach of Röger et al.[3]
– Particle temperatures and energy balance
solved on Eulerian grid
– Gas-particle heat transfer modeled with
Ranz-Marshall correlation:
– Improved internal curtain heat-exchange
derived between 2 semi-transparent surfaces
[3] Röger, M. et al. (2011). J. of Sol. Energy Eng., 133.
ṁp
hp(Tin,f)
ṁp
hp(Tin,b)
ṁp,f
hp(Tf)
ṁp,b
hp(Tb)
frad,Q
fconv,Q
fsol,Q
bsol,Q
curtQ
brad,Q
bconv,Q
iiiλiλ
M
m iλiλ
iλiλ
curt yxfTfTσ
ρρ
εε
Q ΔΔ∑
-1
,
4
i',
4
i'
1 ',,
',,
mm
mm
mm
curtconvsolradp,inoutp, QQQQhhmp
3/12/1
PrRe6.02 gp
p
pp
k
dh
Nu
9
10. University of Maryland, College Park
Radiation Transport Model
• Radiation balance solved via surface-to-surface radiation method
– Hottel’s zonal method[3] is employed for semi-transparent cells with view
factors calculated from Gaussian Integration
– Curtain transmittance τrad depends on particle
diameter dp and volume fraction fv:
curt
p
v
rad z
d
f
τ Δ
2
3
exp
𝜹 𝒌𝒋 𝒒 𝒐𝒖𝒕,𝝀 𝒎,𝒊
′′
= 𝝆 𝝀 𝒎,𝒊 𝒒𝒊𝒏𝒄,𝝀 𝒎,𝒊
′′
+ 𝝉 𝝀 𝒎,𝒊 𝒒𝒊𝒏𝒄,𝝀 𝒎,𝒊′
′′
+ 𝜺 𝝀 𝒎,𝒊 𝒇 𝝀 𝒎,𝒊 𝝈𝑻𝒊
𝟒
+ 𝒒 𝒔𝒐𝒍𝑹𝒆𝒇𝒍,𝝀 𝒎,𝒊
′′
𝑸 𝒓𝒂𝒅,𝒊 = 𝑨 𝒇
𝒎=𝟏
𝑴
𝜺 𝝀 𝒎,𝒊 𝒒𝒊𝒏𝒄,𝝀 𝒎,𝒊
′′
− 𝜺 𝝀 𝒎,𝒊 𝒇 𝝀 𝒎,𝒊 𝝈𝑻𝒊
𝟒
10
11. University of Maryland, College Park
Ly,r
Ly,a
x
y
z
Prototype-Scale Receiver Model Parameters
Geometry Lx (m) Ly (m) Lz (m)
Receiver – r 1.85 5.00 1.50
Aperture – a 1.00 3.00 -
Curtain – c 1.00 5.00 Δzcurt
Property Units Baseline Range
dp μm 280 [100, 700]
ṁ’p kg s-1m-1 2.0 [1.0, 4.0]
εp
[4] - 0.85 [0.1-1.0]
Tp,in K 600 [300, 1100]
𝒒 𝑺𝒐𝒍𝒂𝒓
′′ kW m-2
1000 [100, 1500]
ρp
[4] kg m-3 3560 -
Cp,p
[4] J kg-1K-1 264+2.07T-1.12e-3T2
[4] Siegel, N., et al. (2010). J. of Sol. Energy Eng., 132.
λ range (μm) εwall,λ
[4]
0-4.5 0.20
4.5-∞ 0.80
11
12. University of Maryland, College Park
ṁ'p = 4.0 kg s-1m-1, Tp,in = 600 K, 𝒒 𝑺𝒐𝒍𝒂𝒓
′′
= 1000 kW m-2, dpart = 600 μm
Left Wall Front Wall Right Wall
Bottom WallTop Wall Rear Wall
Curtain Front Curtain Rear
ṁ'p = 4.0 kg s-1m-1, Tp,in = 600 K, 𝒒 𝑺𝒐𝒍𝒂𝒓
′′
= 1000 kW m-2, dpart = 100 μm
Left Wall Front Wall Right Wall
Bottom WallTop Wall Rear Wall
Curtain Front Curtain Rear
ṁ'p = 4.0 kg s-1m-1, Tp,in = 600 K, 𝒒 𝑺𝒐𝒍𝒂𝒓
′′
= 1000 kW m-2, dpart = 280 μm
Left Wall Front Wall Right Wall
Bottom WallTop Wall Rear Wall
Curtain Front Curtain Rear
Prototype Receiver Wall and Curtain Temperatures
Wall Temperatures Particle Temperatures
12
13. University of Maryland, College Park
• Smaller dp decreases curtain τrad
– Lower velocity due to greater
drag increases fv
• For smaller dp where τrad < 0.25,
ηsolar remains constant at ~84%
Impact of dp on Receiver Performance
0.65
0.70
0.75
0.80
0.85
440
460
480
500
520
540
100 200 300 400 500 600 700
ηsolar
ΔTp(K)
dp (μm)
dp (μm)
13
14. University of Maryland, College Park
Directly Irradiated
Zone
Directly Irradiated
Zone
ṁ'p
(kg s-1m-1)
0.0
0.2
0.4
0.6
0.8
1.0
500
700
900
1100
1300
1500
0 10 20 30 40
ηSolar
OutletTp(K)
ṁ'p (kg s-1m-1)
Particle, rear
Particle, front
Efficiency
ṁ'p
(kg s-1m-1)
• Increasing ṁ'p transmit reduces light to rear of the curtain and to
back walls.
• This increases ηsolar to maximum of ~ 88% at the expense of lower
Tp,out and higher T-gradients between front and rear of the curtain.
• Optimal flow-rate between 8 and 10 kg s-1m-1 achieve near maximum
ηsolar at higher Tp,out.
Impact of ṁ'p on Performance
14
15. University of Maryland, College Park
• Prototype-scale results demonstrate need for high flow rates and
longer falls to achieve higher Tp,out while maintaining high ηsolar.
• Sandia National Labs[5] have been studying large, commercial-scale
receivers at their solar field facility.
• It is important to assess performance trade-offs at these larger
commercial scales before large-scale investments can be made for
plants using particle receivers.
• Commercial-scale receiver design requires evaluation of important
operating parameters for further development
– Impact of εp on performance
– Advantages of selective absorption, with εp in solar spectra and low εp at
longer wavelength
Commercial-scale Particle Receiver Simulations
[5] Ho,C. (2014). Personal Communication.
15
16. University of Maryland, College Park
Ly,r
Ly,a
x
y
z
Commercial-Scale Receiver Model Parameters
Geometry Lx (m) Ly (m) Lz (m)
Receiver – r 12 21 15
Aperture – a 11 20 -
Curtain – c 11 21 tcurt
Property Units Baseline
dp μm 280
ṁ’p kg s-1m-1 40
ρp
[4] kg m-3 3560
Cp,p
[4] J kg-1K-1 264+2.07T-1.12e-3T2
Tp,in K 600
𝒒 𝑺𝒐𝒍𝒂𝒓
′′ kW m-2
1000
16
λ range (μm) εp,λ εwall,λ
[4]
0-2.5 0.1-0.9 0.2
2.5-4.5 0.1-0.9 0.2
4.5-∞ 0.1-0.9 0.8
17. University of Maryland, College Park
• ηsolar and Tp,out both increase
monotonically with εp
• Due to high ṁ'p, minimal
solar irradiation reaches rear
of curtain.
Impact of Grey Particle Emissivity on Performance
0.0
0.2
0.4
0.6
0.8
1.0
500
700
900
1100
1300
1500
0.1 0.3 0.5 0.7 0.9
ηSolar
Tp(K)
εp (-)
Front Temperature
Rear Temperature
Efficiency
17
18. University of Maryland, College Park
Solar Irradiance and Particle Emittance
0
300
600
900
1,200
1,500
1,800
250 750 1250 1750 2250 2750 3250 3750
SpectralIrradiance/Emittance(Wm-2nm-1)
Wavelength (nm)
Solar Source 5600 K Source
1000 K Blackbody 1300 K Blackbody
1600 K Blackbody 1900 K Blackbody
0
100
200
300
1750 2250 2750 3250 3750
18
19. University of Maryland, College Park
ṁ'p = 40 kg s-1m-1, Tp,in = 600 K, 𝒒 𝑺𝒐𝒍𝒂𝒓
′′
= 1000 kW m-2, dpart = 280 μm
εp,λ<2.5μm=0.90, εp,λ>2.5μm=0.50
ṁ'p = 40 kg s-1m-1, Tp,in = 600 K, 𝒒 𝑺𝒐𝒍𝒂𝒓
′′
= 1000 kW m-2, dpart = 280 μm
εp,λ<2.5μm=0.90, εp,λ>2.5μm=0.90
ṁ'p = 40 kg s-1m-1, Tp,in = 600 K, 𝒒 𝑺𝒐𝒍𝒂𝒓
′′
= 1000 kW m-2, dpart = 280 μm
εp,λ<2.5μm=0.90, εp,λ>2.5μm=0.10
Impact of Particle IR Emissivity on Temperatures
19
20. University of Maryland, College Park
Performance
Measure
Units
IR emissivity (λ > 2.5 μm)
ελ = 0.1 ελ = 0.3 ελ = 0.5 ελ = 0.7 ελ = 0.9
ηSolar (-) 0.892 0.888 0.884 0.881 0.878
ηgas (-) 0.005 0.005 0.005 0.005 0.005
ηrad,lost (-) 0.090 0.094 0.098 0.101 0.104
ηconv,lost (-) 0.012 0.012 0.012 0.013 0.013
Tp,out (front) K 1307 1303 1300 1296 1294
Tp,out (rear) K 648 648 648 648 648
Impact of Particle IR Emissivity on Receiver Performance
Results for Inlet Tp,in = 600 K with ελ<2.5 = 0.9
20
21. University of Maryland, College Park
Outline
• Background
• Inert Particle Receiver Simulations
– Model description
– Prototype-scale results
– Commercial-scale results
• Reactive Particle Receiver Simulations
– Reactive particle modeling
– Ceria particle results
– Perovskite particle results
• Reactive Particle Receiver CFD Simulations
– Reactive particle modeling
– Ceria particle results
– Comparison of simplified and CFD model
21
22. University of Maryland, College Park
• Undoped and doped ceria has been proposed by many authors[6-10]
for solar thermochemical fuel production because it:
– Preserves its (flourite) crystal structure under large degrees of
reduction, δ
– Maintains thermal stability with melting temperature >2800 K
– Exhibits high catalytic activity for H2O and CO2 reduction
• Lab-scale tests have demonstrated the capability to reliably yields H2
or CO, but have had trouble identifying practical receiver geometries
Ceria as a Solar Material
Parameter Value
ρpart (kg/m3)
7215 (Ce2O4)
6200 (Ce2O3)
cp,part (J/kg-K) ~460[11]
kpart (W/m-K) 12.0[11]
λ range
(μm)
frad (%)
Solar
εp,λ
[10]
Solar
frad (%)
1600 K
εp,λ
[10]
1600K
0-0.6 31 0.57 0 0.36
0.6-1.25 54 0.26 7 0.17
1.25-3.5 15 0.09 64 0.08
3.5-∞ 0 0.51 29 0.34
[6] Chueh, W, & Haile, S. (2010) Phil. Trans. Roy. Soc A, 368.
[7] Scheffe, J., Steinfeld, A. (2012) Energy & Fuels, 26.
[8] Lapp et al. (2012) Energy, 37.
[9] Le Gal et al. (2011). Energy & Fuels, 25.
[10] Marabelli & Wachter. (1987) Phys. Rev. B., 36.
[11] Mogensen et al. (2000). Sol. State. Ion., 129.
22
24. University of Maryland, College Park
0.0001
0.001
0.01
0.1
1
1.E-321.E-281.E-241.E-201.E-161.E-121.E-081.E-041.E+00
δinCeO2-δ
1773
1673
1573
1473
1373
1273
1173
1073
973
873
• Zinkevich et al. (2010) model incorrectly accounted for δ dependence
– Corrected Zinkevich model correctly models T >1000 K
– Corrected Zinkevich model has reasonable low-T performance
• Surface thermodynamics fit ∆𝒉 𝒓𝒆𝒅,𝒔
𝟎
− ∆𝒉 𝒓𝒆𝒅,𝒃
𝟎
and ∆𝒔 𝒓𝒆𝒅,𝒔
𝟎
− ∆𝒔 𝒓𝒆𝒅,𝒃
𝟎
by using in-situ XPS data of DeCaluwe et al. (2011)
Thermodynamic Model
Equilibrium PO2 (atm) compared to experimental values[12]
24
25. University of Maryland, College Park
• Thermodynamics must capture temperature dependence of ideal-
state and excess properties under partially reduced conditions.
– Ideal-state temperature dependence captured with SGTE polynomial
– Ideal entropy of mixing by dilute solution (thermodynamically consistent)
– Non-ideal bulk excess free energy calculated with Redlich-Kister terms
• Chemistry based on reversible mass action kinetics with rates and
excess free energy term modeled as in DeCaluwe et al. (2011)
Ceria Thermochemistry for Reactive Particle Model
25
4
0,
2
32
ln,Δ
OCe
OCeex
red
X
X
RTδTμ
TR
kk
0
red
R1fwd,R1rev, exp
TR
μμμ
TRWπ
P
σk
0
O(s)
0
O
0
(s)V
O
0
OR2fwd,
2O
2
2
5.0
exp
2
δTμδTμTμδTμ ex
red
ex
redredred ,Δ,ΔΔ,Δ 0,0
26. University of Maryland, College Park
Ly,r
Ly,a
x
y
z
Prototype-Scale Receiver Model Parameters
Geometry Lx (m) Ly (m) Lz (m)
Receiver – r 1.85 5.00 1.50
Aperture – a 1.00 3.00 -
Curtain – c 1.00 5.00 tcurt
Property Units Baseline Range
dp μm 300 [200, 700]
ṁ’p kg s-1m-1 2.0 [1.0, 4.0]
Tp,in K 1100 [1000, 1400]
𝒒 𝑺𝒐𝒍𝒂𝒓
′′ kW m-2
1000 -
PO2,in atm 1·(10-5) -
26
λ range (μm) εwind,λ
[15] ρwind, λ
[15] εwall,λ
[4]
0-0.6 0.00 0.073 0.20
0.6-1.25 0.00 0.071 0.20
1.25-3.5 0.046 0.068 0.20
3.5-∞ 0.91 0.011 0.80
[15] Heraeus. (2007).
27. University of Maryland, College Park
Reactive particle wall temperatures
ṁ'p = 1 kg s-1m-1, Tp,in = 1300 K, 𝒒 𝑺𝒐𝒍𝒂𝒓
′′
= 1000 kW m-2, dpart = 300 μm, σstick=0.75
27
28. University of Maryland, College Park
Directly Irradiated Zone
ṁ'p = 1 kg s-1m-1, Tp,in = 1300 K, 𝒒 𝑺𝒐𝒍𝒂𝒓
′′
= 1000 kW m-2, dpart = 300 μm, σstick=0.75ṁ'p = 1 kg s-1m-1, Tp,in = 1300 K, 𝒒 𝑺𝒐𝒍𝒂𝒓
′′
= 1000 kW m-2, dpart = 300 μm, σstick=0.10
Directly Irradiated Zone
• Ceria is rate-controlled by surface reaction
• Cooling outside directly irradiated zone by radiation loss and reaction
• Lower σstick cases do not reach equilibrium by exit
Impact of varying ceria kinetics
28
29. University of Maryland, College Park
0
0.02
0.04
0.06
XCe2O3(2δ)
Particle Flow Rate (kg s-1m-1)
1 2 3 4
0
0.1
0.2
0.3
ηtot
1300
1500
1700
1900
1000 1100 1200 1300 1400
Tp,out(K)
Tp,in (K)
Impact of varying Inlet Tp
29
30. University of Maryland, College Park
• Smaller particles capture more energy chemically
– Greater surface area and Tp
• Reactive particles can achieve higher ηSolar than inert particles
• Particles much lower than 300 μm can have stability problems[4]
Impact of dp and reaction on performance
Chem
Solar
k
k
Sensible η
Q
hmhm
η
tot
1
kout,kout,kin,kin,
Solar
n
i
ipreac
O
ireactg
Chem
Q
Th
W
m
η
cells
1
,
,,
Δ
2
0
0.05
0.1
0.15
0.2
0.25
100 200 300 400 500 600 700
Efficiency
dP (μm)
ηSensible ηChem ηInert
30
31. University of Maryland, College Park
• Receiver design is not optimized for ceria production
– To achieve high Tp at this scale requires low ṁ'p
• Design requires evaluation in context of a full-system
– Strategies for power production or heat recovery
• Undoped ceria performance is low due to very high Tp and low εp
– Doping strategies being explored, but face challenges due to cycling
and slow oxidation kinetics. [6,8-10]
• Lower-Tp cycles with better optical properties can achieve higher
performance
• Perovskites are a class of materials with similar solid-structures and
high εp
– Favorable reduction thermodynamics at much lower temperatures
– Cannot be used for fuel production
Ceria conclusions and perovskite motivation
31
32. University of Maryland, College Park
Surface Exchange
2 OO(s) ↔ O2(g)+2 VO(s)
ksurf,∞ = 0.109 m/s [18] Ea,surf =74.30 kJ/mol [18]
La0.1Sr0.9Co0.8Fe0.2O3-δ Particle Model
δb
δs
Diffusion
Surf
Exch.
• Species fractions related to δ:
Diffusion
LSCFO3(b) + VO(s) ↔ LSCFO2(b) + OO(s)
D∞ = 1.01e-4 m2/s [18] Ea,diff = 55.96 kJ/mol [18]
dr
μd
TR
ρD
an OOO
partdiff
0
= ( )sseqsurfsurf kn δδρ -,
0
=
Parameter Value
ρpart (kg/m3)
6580[16] (LSCFO3)
6051[16] (LSCFO2)
cp,part (J/kg-K) 145[16]
ε (-) 0.90[17]
[16]: Beale, S. et al. (2011). ECS Transaction, 35: 935-943.
[17]: Guar, A. et al. (2013) Euro. Fuel Cell Conf.
[18]: Choi, M. et al. (2011). Sol. State Ionics, 11: 269-274.
[ ] [ ] ( )
[ ] [ ] δρ
δρ
0
O20.20.80.90.1
0
O30.20.80.90.1
VOFeCoSrLa
1OOFeCoSrLa
==
== -
32
33. University of Maryland, College Park
• Assume ΔHO(δ) and ΔSO(δ) are constant with temperature[19]
• Ideal thermodynamics fit to NASA Polynomial (Ref. state: δ0 =0.45)
LSCF Thermodynamics
ΔHO = -433.27δ - 55.835
ΔSO = -76.414δ - 168.78
1000 °C
950 °C
900 °C
800 °C
1000 °C
950 °C
900 °C
800 °C
OO
eqO
OeqOOLSCFOLSCFO μTμ
P
P
RTTμPTμδTμδTμ Δ
2
1
ln
2
1
,
2
1
,-, 0
0
,0
, 2
2
22223
[19]: Choi, M. et al. (2012). Sol. State Ionics, 12: 22-27.
33
34. University of Maryland, College Park
ṁ'p = 7.0 kg s-1m-1, Tp,in = 800 K, 𝒒 𝑺𝒐𝒍𝒂𝒓
′′
= 1000 kW m-2, dpart = 300 μm, k = ksurf
Directly irradiated zone
ṁ'p = 7.0 kg s-1m-1, Tp,in = 800 K, 𝒒 𝑺𝒐𝒍𝒂𝒓
′′
= 1000 kW m-2, dpart = 300 μm, k = 10* ksurf
Directly irradiated zone
Influence of Reaction Rate
• Process is kinetically limited by surface rates.
• Reduction is driven strongly by Tp, even at high PO2.
• Faster reduction decreases ΔTp and improves efficiency.
34
35. University of Maryland, College Park
Influence of Reaction Rate
1100
1130
1160
1190
1220
1250
200 300 400 500 600
Tp,out(K)
dP (μm)
k x 10 k x 1
• ηSolar is relatively constant at both kinetic rates
• ηChem increases while ηSensible decreases with faster kinetics
• Smaller dp particle curtains have lower τ, greater surface area, and
slower up
• With faster kinetics, ηSensible actually decreases with dp
0
0.2
0.4
0.6
0.8
1
200 300 400 500 600
StorageEfficiency
dP (μm)
k x 10 - ηSolar k x 10 - ηChem
k x 1 - ηSolar k x 1 - ηChem
35
36. University of Maryland, College Park
• LSCF transmits more than inert particles at higher ṁ'p due to higher ρ
• Transition in temperature curve ~1000 K due to reaction
• Tradeoff between higher ṁ'p and higher Tp shows inflection in O2
production around 20 kg s-1m-1
Commercial-scale, influence of ṁ'p
36
ṁ'p
(kg s-1m-1)
ṁ'p
(kg s-1m-1)ṁ'p
(kg s-1m-1)
37. University of Maryland, College Park
• LSCF tests demonstrate significant potential to improve storage
density significantly via chemical reduction
• LSCF equilibrium show strong Tp dependence large ΔSO desirable
• Reactive particles require careful consideration of storage conditions
• Ideal operation requires evaluation in full-cycle context
Perovskite conclusions
0
400
800
1200
1600
0.0
0.2
0.4
0.6
0.8
1.0
20 30 40 50 60 70 80
OutletTp(K)
Efficiency
ṁ'p (kg s-1m-1)
37
38. University of Maryland, College Park
Outline
• Background
• Inert Particle Receiver Simulations
– Model description
– Prototype-scale results
– Commercial-scale results
• Reactive Particle Receiver Simulations
– Reactive particle modeling
– Ceria particle results
– Perovskite particle results
• Reactive Particle Receiver CFD Simulations
– Reactive particle modeling
– Ceria particle results
– Comparison of simplified and CFD model
38
39. University of Maryland, College Park
• Validate simplified model assumptions
– Gas entrainment model developed for non-reactive, isothermal flow
– Curtain stability untested with simplified model
• Evaluate impact of gas-flow on performance
– Internal gas-flow impacts wall and particle temperatures through
recirculation
• Test alternative gas-flow conditions for improvements
– Opportunity to improve O2 injection in vicinity of reaction
– Improved thermal impacts of gas
CFD Model Motivations
39
40. University of Maryland, College Park
• Lagrangian-frame particle tracking
• Particle temperatures and reaction integrated along the fall
• Gas-phase coupling
• Stochastic particle tracking to account for turbulent dispersions
Particle Model
44
1
,, Δ pRppreacreacpgpp
N
m
p
mpmp TTσεahnTTha
dt
dT
cm
m
cell
mm
drops
pY
m
V
t
Wn
n
N
dS
Δ
cell
ipmmpipig
pD
ppdrops
pM
i
V
t
uWnmuu
C
dρ
μ
n
N
dS
Δ
24
Re18
,,,2
cell
refmpmmgppp
drops
pT
V
t
ThThnTTha
n
N
dS
Δ00
p
gpi
ipig
pD
pp
ip
ρ
ρρg
uu
C
dρ
μ
dt
du
,,2
,
24
Re18
40
41. University of Maryland, College Park
• To implement in CFD framework, kinetic mechanism modified to
depend on degree of surface reduction (δs)
• Simplified model shows δs stays in equilibrium with δb.
• Optimization method calculates δs in equilibrium with δb.
Modified Ceria Reaction Mechanism
spsredbpbredsb δTμδTμμ ,Δ,ΔΔ ,,
Profiles of Tp and δ for bulk and surface along fall
41
42. University of Maryland, College Park
• Solves for radiation intensity, Iλ, at every location and in specified
directions, θ and φ
• Directions determined by splitting Cartesian grid into Nθ x Nφ
discretizations in each octant
• Particle source terms determined by collecting contributions from
each injection
Discrete Ordinates (DO) Radiation Model
')'(',,, , ΩΦ
4
4
0
2
dsssrI
π
σ
SrInasrIσaassrI
π
λ
pI
pλλbλλppλλ
cell
pp
drops
p
p
V
t
εd
π
n
N
da
Δ
4
2
cell
pσp
drops
p
p
V
t
εfd
π
n
N
σd
Δ
11
4
2
cell
pppλ
drops
pI
pλ
V
t
Tεaf
n
N
dS m
Δ4
,
Property Value
𝒒 𝑺𝒐𝒍𝒂𝒓
′′
(kW m-2) 917.8
Beam Direction [0, 0, -1]
Beam Width
Δθ x Δφ (deg)
0.001 x 0.001
Diffuse Fraction 0.0
Property Value
Nθ x Nφ 9 x 5
𝑵 𝜽 𝒑
x 𝑵 𝝋 𝒑 7 x 7
Δλ1 (μm) [0, 4.5]
Δλ2 (μm) [4.5, 100]
42
43. University of Maryland, College Park
Prototype-Scale Run Parameters
Lx (m) Ly (m) Lz (m)
Receiver – r 1.85 5.00 1.50
Aperture – w 1.00 3.00 -
Curtain – c 1.00 - 0.01
Gas Inlet - i 1.00 - 0.10
Property Units Baseline Range
dpart μm 300 [200, 500]
ṁ'part kg s-1m-1 2.0 [2.0, 4.0]
Tin K 1100 -
εp - 0.3347 -
PO2,in atm 1·(10-5) -
ug,in m/s 1.0 -
𝒒 𝑺𝒐𝒍𝒂𝒓
′′ kW m-2
917 -
λ range (μm) εWall,λ
[4]
0-4.5 0.20
4.5-∞ 0.80 Lc,z
Li,z
Lc,x
Lagrangian Particle Injection
Locations
43
45. University of Maryland, College Park
• Gas recirculation cells form due to particle-entrainment and buoyancy
• Tg greater than Tp in early fall, less than Tp in later half
• Minimal backflow occurs around edges of curtain
Gas Profiles
45
46. University of Maryland, College Park
• Higher ṁ'p reduces temperatures
– Lowers thermodynamic forcing
– Slows kinetics
• δeq falls due to lower Tp and
increasing PO2
• Higher ṁ'p releases more O2
despite lower δ
Impact of varying ṁ'p (kg s-1m-1)
0.025
0.020
0.015
0.010
0.005
0.000
0 1 2 3 4 5
Meanδp(-)
Distance from inlet (m)
0.04
0.03
0.02
0.01
0.000 1 2 3 4 5
PO2(atm)
Distance from inlet (m)
1900
0 1 2 3 4 5
1100
1300
1500
1700
MeanTp(K)
Distance from inlet (m)
46
47. University of Maryland, College Park
• Gas recirculation
– Pre-heats particles along first half
of fall
– O2 from exit recirculates to inlet
• Higher gas flow-rate around
particles in CFD
– Dampens PO2 rise from reaction
• Higher max Tp with CFD model
– δb reaches equilibrium before exit
– Cooling damped by reoxidiation
outside directly irradiated zone
Comparison of Simplified and CFD Models
CFD Model
Simplified Model
47
48. University of Maryland, College Park
• Higher ṁg impact gas absorption and wall temperatures
• Isotropic radiation reduces reflection out of window
• Higher Tp increases chemical storage
Comparison of Simplified and CFD Models
0.0
0.2
0.4
0.6
0.8
1.0
2.0 3.0 4.0
ṁ'p (kg s-1m-1)
0.0
0.2
0.4
0.6
0.8
1.0
2.0 3.0 4.0
FractionQSolar
ṁ'p (kg s-1m-1)
CFD Model Simplified Model
48
49. University of Maryland, College Park
• Gas injected at the bottom of the receiver near the front and rear wall
– Promotes curtain stability
– Pre-heats entrained gas
Impact of Alternative Gas Injection Strategies
49
50. University of Maryland, College Park
Impact of Alternative Gas Injection Strategies
2100
2000
1900
1800
1700
1600
1500
1400
1300
1200
1100
Temperature(K)
Top
Injection
Bottom
Injection
.020
.018
.016
.014
.012
.010
.008
.004
.002
.000
δb(-)
Top
Injection
Bottom
Injection
Curtain Temperatures Curtain Reduction
50
51. University of Maryland, College Park
• Smaller particles are more efficient
– Below dp ~200 μm, minimal improvement in performance
• Trade-off between ηSolar, mean Tp, and Tp,front-Tp,rear with increasing ṁ'p
– Ideal ṁ'p of 8-10 kg s-1m-1 to balance ηSolar and mean Tp
• Ideal flow values relate to curtain τ, with optimal τ <25% to achieve
higher Tp with minimal changes in ηSolar
• Important to maximize εp, but ideal selectivity improves ηSolar < 2% for
Tp below 1300 K
– At temperature above 1600 K, selectivity can improve ηSolar ~ 5%
Conclusions – Inert Particles
0
0.2
0.4
0.6
0.8
1
600 800 1000 1200 1400 1600
ηSolar
Tp,out (K)
dp
Tp,in
𝑞 𝑆𝑜𝑙𝑎𝑟
′′
εp
51
52. University of Maryland, College Park
• General reactive-particle conclusions:
– Particle size is even more important due to lower τ and higher surface
area
– Best performance occurs when reaction cycle is properly scaled to
particle reaction-rate
– Reactors require analysis in context of a full-cycle to optimize
• Ceria operating Tp is too high and εp too low: Max ηChem ~ 7%
– At maximum ceria ηSolar ~ 35%, the ηChem < 1%
• Perovskite particles show promise due to low reduction Tp , high εp,
and ability to work above atmospheric PO2
• CFD simulations demonstrate the importance of capturing gas-flow
effects
Conclusions – Reactive Particles
52
53. University of Maryland, College Park
• Test new materials
– Perovskites and other dark materials with fast kinetics, low reduction Tp,
and lower cost
• Receiver architectural changes
– Shorter particle drops
– Layered curtains
– Investigate more alternative gas-injection strategies
• Improvements to simplified model
– Improved gas-treatment to include influence of gas over larger range
– Semi-empirical gas flow along walls to capture recirculation
• Improvements to CFD model
– Improve particle-radiation coupling to allow for multi-bin particle
properties and anisotropic scattering
Future Work
53
54. University of Maryland, College Park
• Presentations
– Concentrated Solar Thermal Energy for H2O and CO2 Splitting. Oles, Jackson, Thamire, Gibbons.
ASME-ES2012
– Simulation of High-Temperature Receivers Using Ceria Particles. Oles, Jackson, Gibbons. ASME-
ES2013
– Simulation of High-Temperature Receivers Using LSCF Particles. Oles, Jackson. ASME-ES2014
– Impacts of Spectral Selectivity in Directly Irradiated Particle Receivers. Oles, Jackson, Ho. ASME-
ES2014
• Publications
– Parametric design modeling of concentrated-solar falling-particle receivers. Oles, Jackson. WIP.
– Investigation of absorption selectivity on concentrated-solar falling-particle receiver performance. Oles,
Jackson, Ho. WIP.
– Modeling of a concentrated-solar falling-particle receiver for ceria reduction. Oles, Jackson. Solar
Energy.
– Modeling of storage enhancement in a falling-particle solar receiver utilizing reactive perovskite
particles. Oles, Jackson. WIP
– Modeling reactive ceria particles in a falling-particle solar receiver using CFD. Oles, Jackson. WIP.
Presentations and Publications
54
55. University of Maryland, College Park
• Thank you to Dr. Gregory Jackson for his help and direction as my
Ph.D. advisor.
• Thank you to Warren Citrin for financial support through the Warren
Citrin Fellowship for Entrepreneurial Engineering Students
• Thank you to my dissertation committee – Dr. Kiger, Dr. Riaz, Dr.
Sunderland, and Dr. Zachariah – for your time and scrutiny of this
work.
• Thank you to Dr. Cliff Ho at Sandia Natl. Labs for his collaboration
and direction.
• Thank you to my lab-mates including Will Gibbons, Lei Wang, Josh
Pearlman, Babak Eslami, Danica Gordon, and Esteban Echeverria.
• Thanks to Amanda and my family for their support and
encouragement to make this possible.
Acknowledgements
55