International Scientific Journal


The present paper goal is to compile a comprehensive database of data on the pressure drop and flow distribution uniformity utilizing CFD in a network of parallel tubes arranged in a Z configuration adopted for flat plate solar collectors. A 3-D CFD model is implemented to simulate such a system as in the market, including two domains: tube materials and fluid, besides entering, and exiting prolonged ports. The model specifications are Z disposition of uniform inlet and outlet headers diameter (D = 20 mm), length of 1150 mm, and tube length of 1780 mm. The investigated design parameters include the number of tubes (N = 5, 10, and 15) and the tubes diameter to header diameter ratio (d/D = 0.25, 0.35, and 0.50). For a wide range of inlet Reynolds numbers from 500-5000. The present model demonstrated noticeable agreement with offered experimental findings from the literature. The results affirmed that lowering both the number of tubes and the diameter of tubes enhances the flow distribution uniformity. The findings indicate that lowering the number of tubes from 15 to 5 at a lower tubes diameter to header diameter ratio of of 0.25 at a higher Reynolds number yields a maximum increase in flow distribution uniformity of roughly 180% with a negative effect on the total pressure drop.
PAPER REVISED: 2023-01-10
PAPER ACCEPTED: 2023-02-06
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THERMAL SCIENCE YEAR 2023, VOLUME 27, ISSUE Issue 5, PAGES [4049 - 4061]
  1. Prakasam, M. J. S., et al., An Experimental Study of the Mass-Flow Rates Effect on Flat-Plate Solar Water Heater Performance Using Al2O3/Water Nanofluid, Thermal Science, 21 (2017), Suppl. 2, S379-S388
  2. Noghrehabadi, A., et al., An Experimental Study of the Thermal Performance of the Square and Rhombic Solar Collectors, Thermal Science, 22 (2018), 1B, pp. 487-494
  3. Korres, D. N., Tzivanidis, C., Thermal Analysis of a Serpentine Flat Plate Collector and Investigation of the Flow and Convection Regime, Thermal Science, 23 (2019), 1, pp. 47-59
  4. Charoensawan, P., et al., Flat Plate Solar Water Heater with Closed-Loop Oscillating Heat Pipes, Thermal Science, 25 (2021), 5A, pp. 3607-3614
  5. Hashemian, M., et al., Effect of Various Configurations of Swirl Generator System on the Hydrothermal Performance of the Flat-Plate Solar Collector, Alexandria Engineering Journal, 66 (2023), 03, pp. 573-595
  6. Rimar, M., et al., Analysis and CFD Modelling of Thermal Collectors with a Tracker System, Energies, 15 (2022), 6586
  7. Fatahian, H., et al., Improving the Flow Uniformity in Compact Parallel-Flow Heat Exchangers Manifold Using Porous Distributors, Journal of Thermal Analysis and Calorimetry, 147 (2022), July, pp. 12919-12931
  8. Twaha, S., et al., Applying Grid-Connected Photovoltaic System as Alternative Source of Electricity to Supplement Hydro Power Instead of Using Diesel in Uganda, Energy, 37 (2012), 1, pp. 185-194
  9. Salah El-Din, M. M., On the Optimization of Solar-Driven Refrigerators, Renewable Energy, 20 (2000), 1, pp. 87-93
  10. Abdullah, A. A., et al., Measurements of the Performance of the Experimental Salt-Gradient Solar Pond at Makkah one Year after Commissioning, Solar Energy, 150 (2017), 1, pp. 212-219
  11. Abdel Dayem, A. M., AlZahrani, A., Psychometric Study and Performance Investigation of an Efficient Evaporative Solar HDH Water Desalination System, Sustainable Energy Technologies and Assessments, 52A (2022), 102030
  12. Hassan, M. K., et al., Investigation the Performance of PV Solar Cells in Extremely Hot Environments. Journal of Umm Al-Qura University for Engineering and Architecture, 13 (2022), Sept., pp. 18-36
  13. Weitbrecht, V., et al., Flow Distribution in Solar Collectors with Laminar Flow Conditions, Solar Energy, 73 (2002), 6, pp. 433-441
  14. Duffie, J. A., Beckman, W. A., Solar Engineering of Thermal Processes, in: Flat Plate Collectors, 4th ed., Chapter 6, John Wiley and Sons, Inc, New York, USA, 2013, pp. 236-321
  15. Bassiouny, M. K., Martin, H., Flow Distribution and Pressure Drop in Plate Heat Exchangers - I U Configuration, Chem. Eng. Sci., 39 (1984), 4, pp. 693-700
  16. Bassiouny, M. K., Martin, H., Flow Distribution and Pressure Drop in Plate Heat Exchangers - II Z Configuration, Chem. Eng. Sci., 39 (1984b), 4, pp. 701-704
  17. Jones, G. F., Lior, N., Flow Distribution in Manifold Solar Collectors with Negligible Buoyancy Effects, Solar Energy, 52 (1994), 3, pp. 289-300
  18. Ahn, H., et al., Flow Distribution in Manifolds for Low Reynolds Number Flow, KSME International Journal, 12 (1998), 1, pp. 87-95
  19. Maharudrayya, S., et al., Flow Distribution and Pressure Drop in Parallel-Channel Configurations of Planar Fuel Cells, Journal Power Sources, 144 (2005), 1, pp. 94-106
  20. Fan, J., et al., Flow Distribution in a Solar Collector Panel with Horizontally Inclined Absorber Strips Solar Energy, 81 (2007), 12, pp. 1501-1511
  21. Fang, L., et al., Analytical and Experimental Investigation of Flow Distribution in Manifolds for Heat Exchangers, Journal Hydrodyn, 20 (2008), 2, pp. 179-185
  22. Wang, J., Theory of Flow Distribution in Manifolds, Chem. Eng. J., 168 (2011), 3, pp. 1331-1345
  23. Ekramian, E., et al., Numerical Analysis of Heat Transfer Performance of Flat Plate Solar Collectors. Journal of Fluid-Flow, Heat and Mass Transfer Avestia Publishing, 1 (2014), Jan., pp. 38-42
  24. Cruz-Peragon, F., et al., Characterization of Solar Flat Plate Collectors, Renewable and Sustainable Energy Reviews, 16 (2012), 3, pp. 1709-1720
  25. Hassan, J. M., et al., Modelling the Uniformity of Manifold with Various Configurations, Hindawi Publishing Corporation Journal of Fluids, 2014 (2014), 10, 325259
  26. Facao, J., Optimization of Flow Distribution in Flat Plate Solar Thermal Collectors with Riser and Header Arrangements, Solar Energy, 120 (2015), Oct., pp. 104-112
  27. Yang, H., et al., Effect of the Rectangular Exit-Port Geometry of a Distribution Manifold on the Flow Performance, Appl. Therm. Eng., 117 (2017), May, pp. 481-486
  28. Karvounis, P., et al., Numerical and Experimental Study of Flow Characteristics in Solar Collector Manifolds, Energies MDPI, 12 (2019), 1431
  29. Siddiqui, O. K., et al., Flow Distribution in U - and Z -Type Manifolds: Experimental and Numerical Investigation, Arabian Journal for Science and Engineering, 45 (2020), June, pp. 6005-6020
  30. Karali, M. A., et al., Influence of Using Different Tapered Longitudinal Section Manifolds in a Z Shaped Flat Plate Solar Collector on Flow Distribution Uniformity, Case Studies in Thermal Engineering, 33 (2022), 101922
  31. Incropera, F., Dewitt P. D., Introduction Heat Transfer, 6th edition, John Wiley and Sons Inc., New York USA, 2011

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