Дисертації з теми "Supercritical CO2 power cycle"
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Freas, Rosemarv M. "Analysis of required supporting systems for the Supercritical CO2 power conversion system." Thesis, Cambridge Massachusetts Institute of Technology, 2007. http://hdl.handle.net/10945/2992.
Повний текст джерелаContract number: N62271-97-G-0026.
US Navy (USN) author
Zhao, Qiao. "Conception and optimization of supercritical CO2 Brayton cycles for coal-fired power plant application." Thesis, Université de Lorraine, 2018. http://www.theses.fr/2018LORR0080/document.
Повний текст джерелаEfficiency enhancement in power plant can be seen as a key lever in front of increasing energy demand. Nowadays, both the attention and the emphasis are directed to reliable alternatives, i.e., enhancing the energy conversion systems. The supercritical CO2 (SC-CO2) Brayton cycle has recently emerged as a promising solution for high efficiency power production in nuclear, fossil-thermal and solar-thermal applications. Currently, studies on such a thermodynamic power cycle are directed towards the demonstration of its reliability and viability before the possible building of an industrial-scale unit. The objectives of this PhD can be divided in two main parts: • A rigorous selection procedure of an equation of state (EoS) for SC-CO2 which permits to assess influences of thermodynamic model on the performance and design of a SC-CO2 Brayton cycle. • A framework of optimization-based synthesis of energy systems which enables optimizing both system structure and the process parameters. The performed investigations demonstrate that the Span-Wagner EoS is recommended for evaluating the performances of a SC-CO2 Brayton cycle in order to avoid inaccurate predictions in terms of equipment sizing and optimization. By combining a commercial process simulator and an evolutionary algorithm (MIDACO), this dissertation has identified a global feasible optimum design –or at least competitive solutions– for a given process superstructure under different industrial constraints. The carried out optimization firstly base on cycle energy aspects, but the decision making for practical systems necessitates techno-economic optimizations. The establishment of associated techno-economic cost functions in the last part of this dissertation enables to assess the levelized cost of electricity (LCOE). The carried out multi-objective optimization reflects the trade-off between economic and energy criteria, but also reveal the potential of this technology in economic performance
Riotto, Antonio. "Analisi termodinamica di cicli di potenza complessi a CO2 supercritica." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/22430/.
Повний текст джерелаStene, Henrik Sørskår, and Ole Marius Moen. "Power Plant with CO2 Capture based on PSA Cycle." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-26240.
Повний текст джерелаWangen, Dan Jakob. "Life Cycle Assessment of Power Generation Technologies with CO2 Capture." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19393.
Повний текст джерелаGibbs, Jonathan Paul. "Power conversion system design for supercritical carbon dioxide cooled indirect cycle nuclear reactors." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44765.
Повний текст джерела"June 2008."
Includes bibliographical references.
The supercritical carbon dioxide (S-CO₂) cycle is a promising advanced power conversion cycle which couples nicely to many Generation IV nuclear reactors. This work investigates the power conversion system design and proposes several "Third Generation" plant layouts for power ratings ranging between 20 and 1200 MWe for the recompression cycle. A 20 MWe simple cycle layout was also developed. The cycle designs are characterized by a dispersed component layout in which a single shaft turbomachinery train is coupled to parallel arrays of multiple printed circuit heat exchanger modules. This configuration has arrangement benefits in terms of modularity, inspectability, repairability and replaceability. Compared to the prior second generation dispersed layouts, its lower ductwork pressure drop confers approximately 2% higher thermal efficiency. Two alternative S-CO₂ cycle designs for medium power applications were developed using an in-house optimization computer code and Solid Edge software. The first design is a recompression cycle derived from the 300 MWe design developed at MIT for Generation IV reactors. The design employs one turbine, two compressors (main and recompression) working in parallel and two recuperators (high and low temperature) and maximizes cycle efficiency while striving for a small plant footprint. The second design is a simple S-CO₂ power cycle, which has only one turbine, one compressor, and one recuperator. The main focus of the simple S-CO₂ design is cycle compactness and simplicity while achieving still attractive efficiency. Extensive sensitivity studies were performed for both the medium power recompression and simple S-CO₂ cycles to reveal areas for performance improvement, or performance degradation. Cycle efficiency is most sensitive to turbine inlet temperature.
(cont.) Peak cycle pressure is also an important parameter affecting cycle efficiency, although to a smaller extent than turbine inlet temperature. Higher pressure gives higher efficiency, but this gradually saturates around 28 MPa. Other sensitivity studies included turbomachinery performance, cooling water temperature, and heat exchanger fouling and plugging The reference parameters chosen are a 650°C turbine inlet temperature and 20 MPa peak cycle pressure (compressor outlet) because they reach a high thermodynamic efficiency (~/~47-48%) while staying within materials limitations. In order to couple the cycle to many of the Generation IV nuclear reactors a second reference case was chosen with a turbine inlet temperature of 550°C and a peak cycle pressure of 20 MPa.
by Jonathan Paul Gibbs.
S.M.
THORSSON, BJÖRN J., and HADY R. SOLIMAN. "Supercritical Carbon Dioxide Brayton Cycle for Power Generation : Utilizing Waste Heat in EU Industries." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-282919.
Повний текст джерелаIndustrisektorn står för cirka 30% av den globala totala energiförbrukningen och upp till 50% av den går förlorad som spillvärme. Återskapa att spillvärme från industrier och använda det som energikälla är ett hållbart sätt att producera el. Superkritiska CO2 (sCO2) cykler kan integreras med olika värmekällor inklusive spillvärme. Nuvarande litteratur fokuserar främst på cykelens prestanda utan att undersöka systemets ekonomi. Detta beror främst på bristen på tillförlitliga kostnadsberäkningar för cykelkomponenterna. Baserat på nyligen utvecklade kostnadsskalningsmodeller är det möjligt att utföra mer exakta teknikekonomiska studier på dessa system. Detta möjliggör en förskjutning i fokus från cykeleffektivitet till ekonomi som drivkraft för kommersialisering av sCO2 teknologi. Detta arbete syftar till att utveckla en teknisk ekonomisk modell för dessa avfall-värme-till-kraftsystem. Baserat på litteraturen beräknas spillvärme från olika industrier, vilket visar att de fyra industrierna med störst potential för återvinning av spillvärme är cement, järn och stål, aluminium och gaskompressorstationer. Sex olika sCO2 konfigurationer utvecklades och simulerades för dessa fyra industrier. Den teknisk-ekonomiska modellen optimerar för det högsta Net Present Value (NPV) med hjälp av en artificiell bi-kolonialgoritm. Optimeringsvariablerna är pressure levels, delade förhållanden, recuperatorseffektivitet, kondensortemperatur och turbininloppstemperaturen begränsad av värmekällan. Resultaten visar en stor potential för industrier att sänka kostnaderna med detta system. Av de fyra modellerna industrin gav ett återvinningssystem i en järn och stålfabrik den högsta NPV. Resultaten visar att integrationen av sCO2 cykeln i cementindustrin kan bidra till att minska deras spillvärme med 60%, samtidigt som de gör det möjligt för dem att täcka upp till 56% av deras elbehov. Återbetalningsperioden för de fyra branscherna varierar mellan 6 till 9 år. Dessutom är simple recuperated sCO2 cykler med förvärmning mer ekonomiska än recompressioncykler. Trots att recompressioncykler har högre termisk effektivitet, begränsas de av temperaturglidningen i spillvärmeväxlaren. Denna analys kan hjälpa investerare och ingenjörer att fatta mer informerade beslut för att öka effektiviteten och ekonomiska avkastningen på investeringar för sCO2 cykler och värmeåtervinning på industriområden. För att uppmuntra antagandet av superkritiska CO2 cykler krävs en demo tillsammans med mer forskning för högre temperaturapplikationer med särskild uppmärksamhet på mekanisk integritet.
Yang, Chen. "Thermodynamic Cycles using Carbon Dioxide as Working Fluid : CO2 transcritical power cycle study." Doctoral thesis, KTH, Tillämpad termodynamik och kylteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-50261.
Повний текст джерелаQC 20111205
Schroder, Andrew U. "A Study of Power Cycles Using Supercritical Carbon Dioxide as the Working Fluid." University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1461592844.
Повний текст джерелаRieger, Mathias. "Advanced modeling and simulation of integrated gasification combined cycle power plants with CO2-capture." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2014. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-150522.
Повний текст джерелаChen, Huijuan. "The Conversion of Low-Grade Heat into Power Using Supercritical Rankine Cycles." Scholar Commons, 2010. http://scholarcommons.usf.edu/etd/3447.
Повний текст джерелаVidhi, Rachana. "Organic Fluids and Passive Cooling in a Supercritical Rankine Cycle for Power Generation from Low Grade Heat Sources." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5322.
Повний текст джерелаRezazadeh, Fatemeh. "Optimal integration of post-combustion CO2 capture process with natural gas fired combined cycle power plants." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/14349/.
Повний текст джерелаErrey, Olivia Claire. "Variable capture levels of carbon dioxide from natural gas combined cycle power plant with integrated post-combustion capture in low carbon electricity markets." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/33240.
Повний текст джерелаPham, Hong Son. "Investigation of the supercritical CO2 cycle : mapping of the thermodynamic potential for different applications; further understanding of the physical processes, in particular through simulations and analysis of experimental data." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4338.
Повний текст джерелаThis study first evaluates the thermodynamic performance of the supercritical CO2 (sc-CO2) cycle in a large range of heat source temperature, with a focus on the nuclear applications; a thermal efficiency of 45.7% is reported for a Sodium-cooled Fast Reactor. Second, CFD simulations have been performed on a small scale sc-CO2 compressor and results have been confronted positively with the experimental data. Simulation results on a real scale compressor have then revealed some particularities during the compression of a real fluid, providing feedbacks for the component design. In addition, a reliable performance maps approach has been proposed for the sc-CO2 compressor and validated using the CFD results. Finally, an investigation of bubble collapse in the liquid CO2 near the critical point has disclosed the likely absence of detrimental effects. As such, risks of cavitation damage should be low, favoring the compressor operation in the liquid region for cycle efficiency improvement
Toublanc, Cyril. "Amélioration du cycle trans-critique au CO2 par une compression refrodie : évaluations numérique et expérimentale." Phd thesis, Conservatoire national des arts et metiers - CNAM, 2009. http://tel.archives-ouvertes.fr/tel-00465986.
Повний текст джерелаHerraiz, Palomino Laura. "Selective exhaust gas recirculation in combined cycle gas turbine power plants with post-combustion carbon capture." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/23460.
Повний текст джерелаTkachuk, Andriy. "Smíšený tepelný cyklus." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-229753.
Повний текст джерелаMa, Yuegeng [Verfasser], Tatiana [Akademischer Betreuer] Morozyuk, Tatiana [Gutachter] Morozyuk, and Sergio [Gutachter] Mussati. "Optimal design of supercritical carbon dioxide cycle based system for concentrated solar power application / Yuegeng Ma ; Gutachter: Tatiana Morozyuk, Sergio Mussati ; Betreuer: Tatiana Morozyuk." Berlin : Technische Universität Berlin, 2020. http://d-nb.info/1205804978/34.
Повний текст джерелаAlie, Colin. "CO2 Capture With MEA: Integrating the Absorption Process and Steam Cycle of an Existing Coal-Fired Power Plant." Thesis, University of Waterloo, 2004. http://hdl.handle.net/10012/796.
Повний текст джерелаAl-Anfaji, Ahmed Suaal Bashar. "The optimization of combined power-power generation cycles." Thesis, University of Hertfordshire, 2015. http://hdl.handle.net/2299/15485.
Повний текст джерелаGay, Swann. "Elaboration de matrices microcellulaires de polymère biosourcé par la technologie CO², supercritique." Thesis, Angers, 2017. http://www.theses.fr/2017ANGE0007.
Повний текст джерелаIn the present context, where the preservation of resources and sustainable development became the main issues of this century, the production of more efficient and environmentally friendly materials is essential. Thus, this work deals with thedevelopment of biobased polymeric porous matrix using SC-CO2. The use of PLA makes it possible to produce 100% biosourced and biodegradable matrices, while the use of CO2-SC reduces the ecological impact of the shaping processes. In a first step, a parametric study of PLA matrix shaping by a thermal induced phase separation (TIPS) method coupled to CO2 drying was performed. Low density microcellular matrices were obtained with tunable structural and mechanical properties. The whole process was analyze by life cycle assessment and the results showed that SC-CO2 replacing freeze drying has reduced the environmental impact between 50 and 90%. Secondly, a phase separation in situ study by tomography-X synchrotron radiation tomography allowed us to better understand the mechanics of our process. Finally, the last part of this work was devoted to the implementation of a solvent free process, using SC-CO2 as a blowing agent. The results obtained were used to carry out a comparative study of the two processes developed
Rieger, Mathias [Verfasser], Bernd [Akademischer Betreuer] Meyer, Bernd [Gutachter] Meyer, and Michael [Gutachter] Beckmann. "Advanced modeling and simulation of integrated gasification combined cycle power plants with CO2-capture / Mathias Rieger ; Gutachter: Bernd Meyer, Michael Beckmann ; Betreuer: Bernd Meyer." Freiberg : Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2014. http://d-nb.info/1220911925/34.
Повний текст джерелаHe, Junjing. "High temperature performance of materials for future power plants." Doctoral thesis, KTH, Materialvetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-191547.
Повний текст джерелаQC 20160905
Kotze, Johannes Paulus. "Thermal energy storage in metallic phase change materials." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/96049.
Повний текст джерелаENGLISH ABSTRACT: Currently the reduction of the levelised cost of electricity (LCOE) is the main goal of concentrating solar power (CSP) research. Central to a cost reduction strategy proposed by the American Department of Energy is the use of advanced power cycles like supercritical steam Rankine cycles to increase the efficiency of the CSP plant. A supercritical steam cycle requires source temperatures in excess of 620°C, which is above the maximum storage temperature of the current two-tank molten nitrate salt storage, which stores thermal energy at 565°C. Metallic phase change materials (PCM) can store thermal energy at higher temperatures, and do not have the drawbacks of salt based PCMs. A thermal energy storage (TES) concept is developed that uses both metallic PCMs and liquid metal heat transfer fluids (HTF). The concept was proposed in two iterations, one where steam is generated directly from the PCM – direct steam generation (DSG), and another where a separate liquid metal/water heat exchanger is used – indirect steam generation, (ISG). Eutectic aluminium-silicon alloy (AlSi12) was selected as the ideal metallic PCM for research, and eutectic sodium-potassium alloy (NaK) as the most suitable heat transfer fluid. Thermal energy storage in PCMs results in moving boundary heat transfer problems, which has design implications. The heat transfer analysis of the heat transfer surfaces is significantly simplified if quasi-steady state heat transfer analysis can be assumed, and this is true if the Stefan condition is met. To validate the simplifying assumptions and to prove the concept, a prototype heat storage unit was built. During testing, it was shown that the simplifying assumptions are valid, and that the prototype worked, validating the concept. Unfortunately unexpected corrosion issues limited the experimental work, but highlighted an important aspect of metallic PCM TES. Liquid aluminium based alloys are highly corrosive to most materials and this is a topic for future investigation. To demonstrate the practicality of the concept and to come to terms with the control strategy of both proposed concepts, a storage unit was designed for a 100 MW power plant with 15 hours of thermal storage. Only AlSi12 was used in the design, limiting the power cycle to a subcritical power block. This demonstrated some practicalities about the concept and shed some light on control issues regarding the DSG concept. A techno-economic evaluation of metallic PCM storage concluded that metallic PCMs can be used in conjunction with liquid metal heat transfer fluids to achieve high temperature storage and it should be economically viable if the corrosion issues of aluminium alloys can be resolved. The use of advanced power cycles, metallic PCM storage and liquid metal heat transfer is only merited if significant reduction in LCOE in the whole plant is achieved and only forms part of the solution. Cascading of multiple PCMs across a range of temperatures is required to minimize entropy generation. Two-tank molten salt storage can also be used in conjunction with cascaded metallic PCM storage to minimize cost, but this also needs further investigation.
AFRIKAANSE OPSOMMING: Tans is die minimering van die gemiddelde leeftydkoste van elektrisiteit (GLVE) die hoofdoel van gekonsentreerde son-energie navorsing. In die kosteverminderingsplan wat voorgestel is deur die Amerikaanse Departement van Energie, word die gebruik van gevorderde kragsiklusse aanbeveel. 'n Superkritiese stoom-siklus vereis bron temperature hoër as 620 °C, wat bo die 565 °C maksimum stoor temperatuur van die huidige twee-tenk gesmelte nitraatsout termiese energiestoor (TES) is. Metaal fase veranderingsmateriale (FVMe) kan termiese energie stoor by hoër temperature, en het nie die nadele van soutgebaseerde FVMe nie. ʼn TES konsep word ontwikkel wat gebruik maak van metaal FVM en vloeibare metaal warmteoordrag vloeistof. Die konsep is voorgestel in twee iterasies; een waar stoom direk gegenereer word uit die FVM (direkte stoomopwekking (DSO)), en 'n ander waar 'n afsonderlike vloeibare metaal/water warmteruiler gebruik word (indirekte stoomopwekking (ISO)). Eutektiese aluminium-silikon allooi (AlSi12) is gekies as die mees geskikte metaal FVM vir navorsingsdoeleindes, en eutektiese natrium – kalium allooi (NaK) as die mees geskikte warmteoordrag vloeistof. Termiese energie stoor in FVMe lei tot bewegende grens warmteoordrag berekeninge, wat ontwerps-implikasies het. Die warmteoordrag ontleding van die warmteruilers word aansienlik vereenvoudig indien kwasi-bestendige toestand warmteoordrag ontledings gebruik kan word en dit is geldig indien daar aan die Stefan toestand voldoen word. Om vereenvoudigende aannames te bevestig en om die konsep te bewys is 'n prototipe warmte stoor eenheid gebou. Gedurende toetse is daar bewys dat die vereenvoudigende aannames geldig is, dat die prototipe werk en dien as ʼn bevestiging van die konsep. Ongelukkig het onverwagte korrosie die eksperimentele werk kortgeknip, maar dit het klem op 'n belangrike aspek van metaal FVM TES geplaas. Vloeibare aluminium allooie is hoogs korrosief en dit is 'n onderwerp vir toekomstige navorsing. Om die praktiese uitvoerbaarheid van die konsep te demonstreer en om die beheerstrategie van beide voorgestelde konsepte te bevestig is 'n stoor-eenheid ontwerp vir 'n 100 MW kragstasie met 15 uur van 'n TES. Slegs AlSi12 is gebruik in die ontwerp, wat die kragsiklus beperk het tot 'n subkritiese stoomsiklus. Dit het praktiese aspekte van die konsep onderteken, en beheerkwessies rakende die DSO konsep in die kollig geplaas. In 'n tegno-ekonomiese analise van metaal FVM TES word die gevolgtrekking gemaak dat metaal FVMe gebruik kan word in samewerking met 'n vloeibare metaal warmteoordrag vloeistof om hoë temperatuur stoor moontlik te maak en dat dit ekonomies lewensvatbaar is indien die korrosie kwessies van aluminium allooi opgelos kan word. Die gebruik van gevorderde kragsiklusse, metaal FVM stoor en vloeibare metaal warmteoordrag word net geregverdig indien beduidende vermindering in GLVE van die hele kragsentrale bereik is, en dit vorm slegs 'n deel van die oplossing. ʼn Kaskade van verskeie FVMe oor 'n reeks van temperature word vereis om entropie generasie te minimeer. Twee-tenk gesmelte soutstoor kan ook gebruik word in samewerking met kaskade metaal FVM stoor om koste te verminder, maar dit moet ook verder ondersoek word.
Long, Henry A. III. "Development and Thermodynamic Analysis of an Integrated Mild/Partial Gasification Combined Cycle (IMPGC) Under Green and Brown Field Conditions With and Without Carbon Capture." ScholarWorks@UNO, 2018. https://scholarworks.uno.edu/td/2538.
Повний текст джерелаAlkadee, Dareen. "Techniques de réduction et de traitement des émissions polluantes dans une machine thermique." Phd thesis, Conservatoire national des arts et metiers - CNAM, 2011. http://tel.archives-ouvertes.fr/tel-01005123.
Повний текст джерелаEl, Gemayel Gemayel. "Integration and Simulation of a Bitumen Upgrading Facility and an IGCC Process with Carbon Capture." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/23274.
Повний текст джерелаKhivsara, Sagar D. "A Design Concept of a Volumetric Solar Receiver for Supercritical CO2 Brayton Cycle." Thesis, 2014. http://hdl.handle.net/2005/2996.
Повний текст джерелаCHIOU, FENG REN, and 邱豐壬. "Supercritical CO2 Brayton Cycle Turbine Blade Analysis." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/45712932760899143164.
Повний текст джерела國立清華大學
動力機械工程學系
103
As the fossil fuel consumption is increasing, the energy shortage has gradually become a big problem nowadays. However, the industrial energy utilization is less than 50%, which means almost half of the precious energy is discharged into the air as waste heat or other forms that cannot be further used. The environment is deteriorating, so people are more concerned about the waste heat recovery and the uses of renewable energies (such as geothermal energy). Our laboratory has focused on researches about waste heat recovery system for plants for many years. From subcritical cycle systems (Organic Rankine Cycle, ORC) to supercritical cycle systems (Supercritical CO2 Brayton Cycle), the latter is our main research at present. The reasons for choosing CO2 as working fluid are because of its stability, low critical point conditions, wide range of applications and greenhouse gas reduction. The Turbine-Alternator-Compressor (TAC) component is a very important part in supercritical Brayton cycle system, especially the designs of rotors in compressor and expander, which are extremely difficult. The radial type of rotor is used both in compressor and turbine, and to reduce difficulties, I used the rotor of P-15 jet engine as basic model, but its blade shape still need to be modified corresponding to design points. Then CFD simulation is applied to improve rotor efficiency by repeatedly correct errors. At last, semi-closed system is used to reduce the difficulties of initial test and also for the safety issues.
Lin, Bo Hung, and 林柏宏. "Supercritical CO2 Brayton Cycle Turbine Blade Analysis." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/88439005217672493410.
Повний текст джерела國立清華大學
動力機械工程學系
104
There is a lot of electricity power used for production by industry. degree of electricity produced would consume a pound of coal and release lots of CO2 and wasted heat which cause the global warming、air pollution、acid rain、ozone hole etc. It’s necessary to find the substitute and recycle energy. For recycle energy, many researches changed the direction to supercritical cycle recently. According to the report from Sandia, the America National lab, supercritical Brayton cycle’s heat efficiency can be over 50% which is about 1.25~1.5 times compare to the traditional Rankine cycle. The reason choosing CO2 as working fluid is based on its stability , low critical point condition, wide range of applications and greenhouse gas reduction in the atmosphere. However the compressor and turbine of the system need to be designed precisely. To meet the work conditions of supercritical system, we choose the radial rotor as interior component. Utilize the design procedure built with ANSYS software by the lab graduated student Mr. Chiu to redesign a rotor which could take the high temperature and high pressure (12~18MPa、500~700K) design point. First using the software Aspen Plus to simulate the cycle stations and analyze the workout and efficiency. The design point of the rotor is 1kg/s of mass flowrate and 30000RPM of the rotor velocity to make 14MPa working fluid decrease to about 8MPa and keep the rotor efficiency over 75%. After the theory analysis and design procedure there are two rotor models derived. Although the pressure drop conforms to the design point but the inducer’s effect doesn’t answer to the anticipation and also influence the rotor efficiency to be only 60%. The flaw will be corrected to improve the rotor efficiency and meet the design point.
Liu, Kai-Wen, and 劉凱文. "Supercritical CO2 Brayton Cycle Compressor Blade Design and Analysis." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/ma3872.
Повний текст джерела國立清華大學
動力機械工程學系
105
Accompanied by the prosperity of technology, the electricity needed for production is increasing year to year. However, the overall efficiency is not above 50%, and thus it will produce large amount of carbon dioxide and waste heat. It will give rise to the global warming aggravation and the air pollution, sour rain, ozonosphere holes and the destruction of forest…etc. So this paper intend to find an solution to finding alternative energy and recovery of waste heat, with the increasing literatures focusing on the super critical cycle in the energy recovery field. This paper put aim on the super critical Brayton cycle to make the first compressor design. According to the Sandia Laboratory’ reports, the overall efficiency of the combined cycle can be high above 50%. The reason to use carbon dioxide to be the working fluid is due to its stability, low critical condition, large range of application and capable of reducing the global warming. This paper design the prototype of the blades and rotors of the compressor. And then, by using ANSYS this paper propose a layout of the rotor and blade which can bear high temperature and pressure(7.8~15 MPa, 300~500K). And this model has been verified by comparing the simulation results with the paper [35]. The results are quite similar where the errors are below 6%. The efficiency of the impeller is about 50.1%, compared with the 25% efficiency of the impeller by using Air Ideal Gas as working fluid. It has been proven that the SCO2 compressor impeller is the best choice over the conventional Rankine cycle and the Brayton cycle by Air Ideal Gas. With the advantages of high rotating speed and the low volume, the pressure ratio of this compressor is about 1.85; the efficiency is about 50%.
Wen, Meng-Yang, and 溫孟揚. "Design, Analysis, and Simulation of a Turbine for Supercritical CO2 Brayton Cycle." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/x4838c.
Повний текст джерела國立清華大學
動力機械工程學系
105
The research of Supercritical CO2 (sCO2) Brayton Cycle has been popular over the past decade, due to its higher efficiency and smaller component size compared with those of steam Rankine cycle and air Brayton Cycle. Studies showed that SCO2 Brayton Cycle can accommodate a wide range of temperature as the heat source, starting from 260°C to 1200 °C. Thus, various research had been investigated to apply sCO2 Brayton Cycle into fields such as concentrated solar power, nuclear power, geothermal power, and waste heat recovery, making it a viable option for renewable energy. This study is a subproject of SCO2 Brayton Cycle power generation system, a project under the National Energy Program-Phase II in Taiwan, with the objective of designing a power generation system using waste heat as heat source. The temperature of the waste heat is set to be 450°C, conforming to mid-range waste heat. The aim of this subproject is to design a turbine with the inlet total pressure of 14.1 MPa and total temperature of 573K, respectively, and outlet pressure of 8.5 MPa, corresponding to an expansion ratio of 1.658. Due to its small size and low mass flow rate, radial inflow turbine is selected instead of the axial flow turbine. Some efforts were made by previous member of this lab to modify the existing turbine model to avoid the complexity of designing a turbine model from scratch. The efficiency, however, turned out to be lower the expectation. Therefore, in this study, the previously modified turbine model would be discarded and the new turbine would be built from square one. This study tried to use Meanline Analysis from the literature as a preliminary design tool. Although most studies devoting to the design of radial inflow turbine were developed for turbine using air as working fluid, recent studies about the design of SCO2 turbine indicated that Meanline Analysis is qualified to be a preliminary design tool. The simulation result of the Meanline Analysis was shown to be deviate from the design point, as expected. Fortunately, with the aid of CFD, the problem predicted by the simulation could be corrected and the model could be adjusted accordingly. At the end, with some bold assumption, the turbine model close to the expected pressure ratio and power output was devised.
Lu, Kun Xian, and 盧昆賢. "Analysis of a Supercritical CO2 Rankine Cycle and its Comparison to Organic Rankine Cycles." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/50383888488528634455.
Повний текст джерела國立清華大學
動力機械工程學系
104
About 20% ~ 50% energy is released to environment in the form of waste heat. The waste heat below 250℃ is difficult to recover due to its low thermal energy, but it has large amount and low fuel cost. ORC systems can efficiently convert this low temperature waste heat to electricity. Recently, due to the better heat transfer and low environmental impacts, S-CO2 Rankine cycle has shown pretty good potential in this field. A comparative study of S-CO2 Rankine cycle with R134a and R245fa ORC under 100℃ and 150℃ heat source is included in this study. Considering the pressure effect on performance and costs, the parameter settings for S-CO2 Rankine cycle are targeted on maximum power output. S-CO2 has better temperature matching with heat source so it can utilize heat source energy more efficiently. Besides, the high fluid density of S-CO2 can greatly reduce power unit size. Despite that the net power output per unit mass of working fluid in S-CO2 Rankine cycle is lower than that in ORCs, we can increase the mass flow rate of CO2 to improve the power output because of the very low fluid cost of CO2 compared to organic fluids. In order to realize the competence of S-CO2 Rankine cycle in real market, a comparative study with ORCs from Han Power is also included. Heat source temperature between 90℃~150℃ and inlet pressure of expander under 140 bar are recommended for S-CO2 Rankine cycle. But to commercialize S-CO2 Rankine cycle system, further studies and experiments on real equipment cost and component size are required.
Lin, Sheng-Kuo, and 林聖國. "Configuration Design of A Supercritical CO2 Recompression Brayton Cycle including Impeller Design and CFD Analysis." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/pu25fb.
Повний текст джерелаRieger, Mathias. "Advanced modeling and simulation of integrated gasification combined cycle power plants with CO2-capture." Doctoral thesis, 2013. https://tubaf.qucosa.de/id/qucosa%3A22935.
Повний текст джерелаVan, Rooy Willem. "Solar thermal augmentation of the regenerative feed-heaters in a supercritical Rankine cycle with a coalfired boiler / W.L. van Rooy." Thesis, 2015. http://hdl.handle.net/10394/15901.
Повний текст джерелаMIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2015
Matsuo, Bryce. "A Computational Study on the Thermal-Hydraulic Behavior of Supercritical Carbon Dioxide in Various Printed Circuit Heat Exchanger Designs." Thesis, 2013. http://hdl.handle.net/1969.1/149278.
Повний текст джерелаMartinho, Ana Rita Mota. "Life cycle assessment of a novel CO2 capture technology (hgts) on retrofitting coal and natural gas power plants: portugal case study." Master's thesis, 2020. https://hdl.handle.net/10216/128433.
Повний текст джерелаMartinho, Ana Rita Mota. "Life cycle assessment of a novel CO2 capture technology (hgts) on retrofitting coal and natural gas power plants: portugal case study." Dissertação, 2020. https://hdl.handle.net/10216/128433.
Повний текст джерела