DOI QR코드

DOI QR Code

Design and Performance Analysis of Conical Solar Concentrator

  • Na, Mun Soo (Department of Biosystems Engineering, College of Agriculture and Life Sciences, Kangwon National University) ;
  • Hwang, Joon Yeal (Department of Biosystems Engineering, College of Agriculture and Life Sciences, Kangwon National University) ;
  • Hwang, Seong Geun (Department of Biosystems Engineering, College of Agriculture and Life Sciences, Kangwon National University) ;
  • Lee, Joo Hee (Department of Biosystems Engineering, College of Agriculture and Life Sciences, Kangwon National University) ;
  • Lee, Gwi Hyun (Department of Biosystems Engineering, College of Agriculture and Life Sciences, Kangwon National University)
  • Received : 2018.01.28
  • Accepted : 2018.03.02
  • Published : 2018.03.01

Abstract

Purpose: The objective of this study is to evaluate the performance of the conical solar concentrator (CSC) system, whose design is focused on increasing its collecting efficiency by determining the optimal conical angle through a theoretical study. Methods: The design and thermal performance analysis of a solar concentrator system based on a $45^{\circ}$ conical concentrator were conducted utilizing different mass flow rates. For an accurate comparison of these flow rates, three equivalent systems were tested under the same operating conditions, such as the incident direct solar radiation, and ambient and inlet temperatures. In order to minimize heat loss, the optimal double tube absorber length was selected by considering the law of reflection. A series of experiments utilizing water as operating fluid and two-axis solar tracking systems were performed under a clear or cloudless sky. Results: The analysis results of the CSC system according to varying mass flow rates showed that the collecting efficiency tended to increase as the flow rate increased. However, the collecting efficiency decreased as the flow rate increased beyond the optimal value. In order to optimize the collecting efficiency, the conical angle, which is a design factor of CSC, was selected to be $45^{\circ}$ because its use theoretically yielded a low heat loss. The collecting efficiency was observed to be lowest at 0.03 kg/s and highest at 0.06 kg/s. All efficiencies were reduced over time because of variations in ambient and inlet temperatures throughout the day. The maximum efficiency calculated at an optimum flow rate of 0.06 kg/s was 85%, which is higher than those of the other flow rates. Conclusions: It was reasonable to set the conical angle and mass flow rate to achieve the maximum CSC system efficiency in this study at $45^{\circ}$ and 0.06 kg/s, respectively.

Keywords

References

  1. Al Imam, M. F. I., R. A. Beg, M. S. Rahman and M. Z. H. Khan. 2016. Performance of PVT solar collector with compound parabolic concentrator and phase change materials. Energy and Buildings 113:139-144. https://doi.org/10.1016/j.enbuild.2015.12.038
  2. Ali, A. H. H. 2017. Performance assessment and gained operational experiences of a residential scale solar thermal driven adsorption cooling system installed in hot arid area. Energy and Buildings 138:271-279. https://doi.org/10.1016/j.enbuild.2016.12.062
  3. Cakici, D. M., A. Erdogan and C. O. Colpan. 2017. Thermodynamic performance assessment of an integrated geothermal powered supercritical regenerative organic Rankine cycle and parabolic trough solar collectors. Energy 120:306-319.
  4. Hussein, A. K. 2016. Applications of nanotechnology to improve the performance of solar collectors - Recent advances and overview. Renewable and Sustainable Energy Reviews 62:767-792. https://doi.org/10.1016/j.rser.2016.04.050
  5. Hussain, M. I., A. Ali and G. H. Lee. 2015. Performance and economic analyses of linear and spot Fresnel lens solar collectors used for greenhouse heating in South Korea. Energy 90(2):1522-1531. https://doi.org/10.1016/j.energy.2015.06.115
  6. Hussain, M. I. and G. H. Lee. 2014. Thermal performance evaluation of a conical solar water heater integrated with a thermal storage system. Energy Conversion and Management 87:267-273. https://doi.org/10.1016/j.enconman.2014.07.023
  7. Hussain, M. I. and G. H. Lee. 2015a. Experimental and numerical studies of a U-shaped solar energy collector to track the maximum CPV/T system output by varying the flow rate. Renewable Energy 76:735-742. https://doi.org/10.1016/j.renene.2014.12.008
  8. Hussain, M. I. and G. H. Lee. 2015b. Utilization of solar energy in agricultural machinery engineering: A review. Journal of Biosystems Engineering 40(3):186-192. https://doi.org/10.5307/JBE.2015.40.3.186
  9. Hussain, M. I. and G. H. Lee. 2016. Thermal performance comparison of line- and point-focus solar concentrating systems: Experimental and numerical analyses. Solar Energy 133:44-54. https://doi.org/10.1016/j.solener.2016.03.062
  10. Jaramillo, O. A., M. Borunda, K. M. Velazquez-Lucho and M. Robles. 2016. Parabolic trough solar collector for low enthalpy processes: An analysis of the efficiency enhancement by using twisted tape inserts. Renewable Energy 93:125-141. https://doi.org/10.1016/j.renene.2016.02.046
  11. Kang, M. C., Y. H. Kang, H. K. Yoon and S. Y. Yoo. 2006. A characteristic analysis on the thermal performance of the dish type solar concentrating system. Journal of the Korean Solar Energy Society 26(1):7-12 (In Korean, with English abstract).
  12. Lee, G. H. 2013. A study for the use of solar energy for agricultural industry-solar drying system using evacuated tubular solar collector and auxiliary heater. Journal of Biosystems Engineering 38(1):41-47. https://doi.org/10.5307/JBE.2013.38.1.041
  13. Meng, X., N. Sellami, A. R. Knox, A. Montecucco, J. Siviter, P. Mullen, A. Ashraf, A. Samarelli, L. F. Llin, D. J. Paul, W. Li, M. C. Paul, D. H. Gregory, G. Han, M. Gao, T. Sweet, R. Freer, F. Azough, R. Lowndes, X. Xia and T. K. Mallick. 2016. A novel absorptive/reflective solar concentrator for heat and electricity generation: An optical and thermal analysis. Energy Conversion and Management 114:142-153.
  14. Meiser, S., S. Schneider, E. Lüpfert, B. Schiricke and R. Pitz-Paal. 2015. Evaluation and assessment of gravity load on mirror shape of parabolic trough solar collectors. Energy Procedia 75:485-494. https://doi.org/10.1016/j.egypro.2015.07.434
  15. Park, B. J. and Y. S. So. 1997. A study on the heat collecting performance of solar heat collectors. Review of Architecture and Building Science 21(3):8-12.
  16. Ruelas, J., N. Velazquez and R. Beltran. 2017. Opto-geometric performance of fixed-focus solar concentrators. Solar Energy 141:303-310. https://doi.org/10.1016/j.solener.2016.11.040
  17. Son, P. H., B. W. Park, Y. S. Lee, O. J. Lee, S. H. Choi and S. H. Yoon. 2007. A study of collecting efficiency of flat plate solar collector by collecting angle. Journal of the Korean Society of Marine Engineering 10:163-164.
  18. Tang, F., G. Li and R. Tang. 2016. Design and optical performance of CPC based compound plane concentrators. Renewable Energy 95:140-151. https://doi.org/10.1016/j.renene.2016.04.004
  19. Togrul, İ. T., D. Pehlιvan and C. Akosman. 2004. Development and testing of a solar air-heater with conical concentrator. Renewable Energy 29:263-275. https://doi.org/10.1016/S0960-1481(03)00168-X
  20. Ustaoglu, A., J. Okajima, X. Zhang and S. Maruyama. 2016. Evaluation of the efficiency of dual compound parabolic and involute concentrator. Energy for Sustainable Development 32:1-13. https://doi.org/10.1016/j.esd.2016.02.007
  21. Vijayan, G., M. Vinu Sevastian, K. Umarani and R. Karunakaran. 2013. Design, fabrication and performance study of frusto-conical solar collector by using nanofluids. International Journal of Engineering Research and Technology 2(5): 1220-1226.