Combined Turbine and Cycle Optimization for Organic Rankine Cycle Power Systems—Part A: Turbine Model
Axial-flow turbines represent a well-established technology for a wide variety of power generation systems. Compactness, flexibility, reliability and high efficiency have been key factors for the extensive use of axial turbines in conventional power plants and, in the last decades, in organic Rankin...
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| Format: | Article |
| Language: | English |
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MDPI AG
2016-04-01
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| Series: | Energies |
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| Online Access: | http://www.mdpi.com/1996-1073/9/5/313 |
| _version_ | 1818013405983801344 |
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| author | Andrea Meroni Angelo La Seta Jesper Graa Andreasen Leonardo Pierobon Giacomo Persico Fredrik Haglind |
| author_facet | Andrea Meroni Angelo La Seta Jesper Graa Andreasen Leonardo Pierobon Giacomo Persico Fredrik Haglind |
| author_sort | Andrea Meroni |
| collection | DOAJ |
| description | Axial-flow turbines represent a well-established technology for a wide variety of power generation systems. Compactness, flexibility, reliability and high efficiency have been key factors for the extensive use of axial turbines in conventional power plants and, in the last decades, in organic Rankine cycle power systems. In this two-part paper, an overall cycle model and a model of an axial turbine were combined in order to provide a comprehensive preliminary design of the organic Rankine cycle unit, taking into account both cycle and turbine optimal designs. Part A presents the preliminary turbine design model, the details of the validation and a sensitivity analysis on the main parameters, in order to minimize the number of decision variables in the subsequent turbine design optimization. Part B analyzes the application of the combined turbine and cycle designs on a selected case study, which was performed in order to show the advantages of the adopted methodology. Part A presents a one-dimensional turbine model and the results of the validation using two experimental test cases from literature. The first case is a subsonic turbine operated with air and investigated at the University of Hannover. The second case is a small, supersonic turbine operated with an organic fluid and investigated by Verneau. In the first case, the results of the turbine model are also compared to those obtained using computational fluid dynamics simulations. The results of the validation suggest that the model can predict values of efficiency within ± 1.3%-points, which is in agreement with the reliability of classic turbine loss models such as the Craig and Cox correlations used in the present study. Values similar to computational fluid dynamics simulations at the midspan were obtained in the first case of validation. Discrepancy below 12 % was obtained in the estimation of the flow velocities and turbine geometry. The values are considered to be within a reasonable range for a preliminary design tool. The sensitivity analysis on the turbine model suggests that two of twelve decision variables of the model can be disregarded, thus further reducing the computational requirements of the optimization. |
| first_indexed | 2024-04-14T06:32:46Z |
| format | Article |
| id | doaj.art-a71fa55bcdf049918be0aa60d3370175 |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-04-14T06:32:46Z |
| publishDate | 2016-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-a71fa55bcdf049918be0aa60d33701752022-12-22T02:07:34ZengMDPI AGEnergies1996-10732016-04-019531310.3390/en9050313en9050313Combined Turbine and Cycle Optimization for Organic Rankine Cycle Power Systems—Part A: Turbine ModelAndrea Meroni0Angelo La Seta1Jesper Graa Andreasen2Leonardo Pierobon3Giacomo Persico4Fredrik Haglind5Department of Mechanical Engineering, Technical University of Denmark, Nils Koppels Allé, Building 403, Kongens Lyngby 2800, DenmarkDepartment of Mechanical Engineering, Technical University of Denmark, Nils Koppels Allé, Building 403, Kongens Lyngby 2800, DenmarkDepartment of Mechanical Engineering, Technical University of Denmark, Nils Koppels Allé, Building 403, Kongens Lyngby 2800, DenmarkDepartment of Mechanical Engineering, Technical University of Denmark, Nils Koppels Allé, Building 403, Kongens Lyngby 2800, DenmarkLaboratorio di Fluidodinamica delle Macchine, Dipartimento di Energia, Politecnico di Milano, Via Lambruschini 4, Milan I-20156, ItalyDepartment of Mechanical Engineering, Technical University of Denmark, Nils Koppels Allé, Building 403, Kongens Lyngby 2800, DenmarkAxial-flow turbines represent a well-established technology for a wide variety of power generation systems. Compactness, flexibility, reliability and high efficiency have been key factors for the extensive use of axial turbines in conventional power plants and, in the last decades, in organic Rankine cycle power systems. In this two-part paper, an overall cycle model and a model of an axial turbine were combined in order to provide a comprehensive preliminary design of the organic Rankine cycle unit, taking into account both cycle and turbine optimal designs. Part A presents the preliminary turbine design model, the details of the validation and a sensitivity analysis on the main parameters, in order to minimize the number of decision variables in the subsequent turbine design optimization. Part B analyzes the application of the combined turbine and cycle designs on a selected case study, which was performed in order to show the advantages of the adopted methodology. Part A presents a one-dimensional turbine model and the results of the validation using two experimental test cases from literature. The first case is a subsonic turbine operated with air and investigated at the University of Hannover. The second case is a small, supersonic turbine operated with an organic fluid and investigated by Verneau. In the first case, the results of the turbine model are also compared to those obtained using computational fluid dynamics simulations. The results of the validation suggest that the model can predict values of efficiency within ± 1.3%-points, which is in agreement with the reliability of classic turbine loss models such as the Craig and Cox correlations used in the present study. Values similar to computational fluid dynamics simulations at the midspan were obtained in the first case of validation. Discrepancy below 12 % was obtained in the estimation of the flow velocities and turbine geometry. The values are considered to be within a reasonable range for a preliminary design tool. The sensitivity analysis on the turbine model suggests that two of twelve decision variables of the model can be disregarded, thus further reducing the computational requirements of the optimization.http://www.mdpi.com/1996-1073/9/5/313organic Rankine cycle (ORC)axial turbine designcombined optimizationturbine experimental validationturbine sensitivity analysis |
| spellingShingle | Andrea Meroni Angelo La Seta Jesper Graa Andreasen Leonardo Pierobon Giacomo Persico Fredrik Haglind Combined Turbine and Cycle Optimization for Organic Rankine Cycle Power Systems—Part A: Turbine Model Energies organic Rankine cycle (ORC) axial turbine design combined optimization turbine experimental validation turbine sensitivity analysis |
| title | Combined Turbine and Cycle Optimization for Organic Rankine Cycle Power Systems—Part A: Turbine Model |
| title_full | Combined Turbine and Cycle Optimization for Organic Rankine Cycle Power Systems—Part A: Turbine Model |
| title_fullStr | Combined Turbine and Cycle Optimization for Organic Rankine Cycle Power Systems—Part A: Turbine Model |
| title_full_unstemmed | Combined Turbine and Cycle Optimization for Organic Rankine Cycle Power Systems—Part A: Turbine Model |
| title_short | Combined Turbine and Cycle Optimization for Organic Rankine Cycle Power Systems—Part A: Turbine Model |
| title_sort | combined turbine and cycle optimization for organic rankine cycle power systems part a turbine model |
| topic | organic Rankine cycle (ORC) axial turbine design combined optimization turbine experimental validation turbine sensitivity analysis |
| url | http://www.mdpi.com/1996-1073/9/5/313 |
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