Numerical and Experimental Study of Flow Characteristics in Solar Collector Manifolds
The flow through a forced circulation Z-type flat plate solar collector was investigated by means of combined experimental measurements and numerical simulations. The efficient operation of such collectors depends on the uniformity of the flow rate distribution among their riser tubes, while low pum...
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| Format: | Article |
| Language: | English |
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MDPI AG
2019-04-01
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| Series: | Energies |
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| Online Access: | https://www.mdpi.com/1996-1073/12/8/1431 |
| _version_ | 1811299886397652992 |
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| author | Panagiotis Karvounis Dimitrios Koubogiannis Elias Hontzopoulos Antonios Hatziapostolou |
| author_facet | Panagiotis Karvounis Dimitrios Koubogiannis Elias Hontzopoulos Antonios Hatziapostolou |
| author_sort | Panagiotis Karvounis |
| collection | DOAJ |
| description | The flow through a forced circulation Z-type flat plate solar collector was investigated by means of combined experimental measurements and numerical simulations. The efficient operation of such collectors depends on the uniformity of the flow rate distribution among their riser tubes, while low pumping power demand is also sought. Mass flow rate measurements in the riser tubes were performed, utilizing a specially adapted ultrasound instrument for various values of total flow rates in the collector. By means of a commercial Computational Fluid Dynamics (CFD) code, laminar and turbulent flow models in different computational grids were tested and validated against the experiments. Appropriate metrics were introduced to quantify flow rate distribution non-uniformity among the risers, and pressure drop through the manifold was calculated. Parametric studies for flow conditions outside the experimental window were performed utilizing the CFD method in order to assess the effect of the Reynolds number in the flow distribution among the riser tubes. Furthermore, aiming to enhance flow rate uniformity, a methodology based on modifying the diameter of each riser tube was applied and successfully demonstrated. The proposed method can be employed in large solar collector arrays, either as stand-alone systems or as belonging to hybrid alternative sources of energy (ASE) systems, aiming to optimize their overall efficiency. |
| first_indexed | 2024-04-13T06:43:13Z |
| format | Article |
| id | doaj.art-c81c06a643e44faa955d89dfa6374cd3 |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-04-13T06:43:13Z |
| publishDate | 2019-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-c81c06a643e44faa955d89dfa6374cd32022-12-22T02:57:41ZengMDPI AGEnergies1996-10732019-04-01128143110.3390/en12081431en12081431Numerical and Experimental Study of Flow Characteristics in Solar Collector ManifoldsPanagiotis Karvounis0Dimitrios Koubogiannis1Elias Hontzopoulos2Antonios Hatziapostolou3University of West Attica, Campus 1, School of Engineering, Agiou Spyridonos, 12243 Aigaleo, GreeceUniversity of West Attica, Campus 1, School of Engineering, Agiou Spyridonos, 12243 Aigaleo, GreecePrime Laser Technology SA, Viopa Kerateas, 19001 Keratea, GreeceUniversity of West Attica, Campus 1, School of Engineering, Agiou Spyridonos, 12243 Aigaleo, GreeceThe flow through a forced circulation Z-type flat plate solar collector was investigated by means of combined experimental measurements and numerical simulations. The efficient operation of such collectors depends on the uniformity of the flow rate distribution among their riser tubes, while low pumping power demand is also sought. Mass flow rate measurements in the riser tubes were performed, utilizing a specially adapted ultrasound instrument for various values of total flow rates in the collector. By means of a commercial Computational Fluid Dynamics (CFD) code, laminar and turbulent flow models in different computational grids were tested and validated against the experiments. Appropriate metrics were introduced to quantify flow rate distribution non-uniformity among the risers, and pressure drop through the manifold was calculated. Parametric studies for flow conditions outside the experimental window were performed utilizing the CFD method in order to assess the effect of the Reynolds number in the flow distribution among the riser tubes. Furthermore, aiming to enhance flow rate uniformity, a methodology based on modifying the diameter of each riser tube was applied and successfully demonstrated. The proposed method can be employed in large solar collector arrays, either as stand-alone systems or as belonging to hybrid alternative sources of energy (ASE) systems, aiming to optimize their overall efficiency.https://www.mdpi.com/1996-1073/12/8/1431solar thermal energy modelssolar collector manifold designsolar collector flow distributionuniformity enhancement |
| spellingShingle | Panagiotis Karvounis Dimitrios Koubogiannis Elias Hontzopoulos Antonios Hatziapostolou Numerical and Experimental Study of Flow Characteristics in Solar Collector Manifolds Energies solar thermal energy models solar collector manifold design solar collector flow distribution uniformity enhancement |
| title | Numerical and Experimental Study of Flow Characteristics in Solar Collector Manifolds |
| title_full | Numerical and Experimental Study of Flow Characteristics in Solar Collector Manifolds |
| title_fullStr | Numerical and Experimental Study of Flow Characteristics in Solar Collector Manifolds |
| title_full_unstemmed | Numerical and Experimental Study of Flow Characteristics in Solar Collector Manifolds |
| title_short | Numerical and Experimental Study of Flow Characteristics in Solar Collector Manifolds |
| title_sort | numerical and experimental study of flow characteristics in solar collector manifolds |
| topic | solar thermal energy models solar collector manifold design solar collector flow distribution uniformity enhancement |
| url | https://www.mdpi.com/1996-1073/12/8/1431 |
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