Thermal and hydraulic characteristics of a large-scaled parabolic trough solar field (PTSF) under cloud passages

Abstract

To better understand the characteristics of a large-scaled parabolic trough solar field (PTSF) under cloud passages, a novel method which combines a closed-loop thermal hydraulic model (CLTHM) and cloud vector (CV) is developed. Besides, the CLTHM is established and validated based on a pilot plant. Moreover, some key parameters which are used to characterize a typical PTSF and CV are presented for further simulation. Furthermore, two sets of results simulated by the CLTHM are compared and discussed. One set deals with cloud passages by the CV, while the other by the traditionally distributed weather stations (DWSs). Because of considering the solar irradiance distribution in a more detailed and realistically way, compared with the distributed weather station (DWS) simulation, all essential parameters, such as the total flowrate, flow distribution, outlet temperature, thermal and exergetic efficiency, and exergetic destruction tend to be more precise and smoother in the CV simulation. For example, for the runner outlet temperature, which is the most crucial parameter for a running PTSF, the maximum relative error reaches −15% in the comparison. In addition, the mechanism of thermal and hydraulic unbalance caused by cloud passages are explained based on the simulation.

Key words： parabolic trough solar field (PTSF); thermal hydraulic model; cloud passages; transients

Acknowledgments

This work was supported by the National Key Research and Development Program of China (Grant No. 2018YFB-0905102).

References

1 Yılmaz İ H, Mwesigye A. Modeling, simulation and performance analysis of parabolic trough solar collectors: a comprehensive review. Applied Energy, 2018, 225: 135–174

2 Lippke F. Simulation of the part-load behavior of a 30 MWe SEGS plant. Sandia National Laboratories, Albuquerque, New Mexico, US, Technical report SAND95–1293, 1995

3 Stuetzle T, Blair N, Mitchell J W, Beckman W A. Automatic control of a 30 MW SEGS VI parabolic trough plant. Solar Energy, 2004, 76(1–3): 187–193

4 Patnode A M. Simulation and performance evaluation of parabolic trough solar power plants. Dissertation for the Master Degree, Madison: University of Wisconsin-Madison, 2006

5 Llorente García I, Álvarez J L, Blanco D. Performance model for parabolic trough solar thermal power plants with thermal storage: comparison to operating plant data. Solar Energy, 2011, 85(10): 2443–2460

6 Silva R, Pérez M, Fernández-Garcia A. Modeling and co-simulation of a parabolic trough solar plant for industrial process heat. Applied Energy, 2013, 106: 287–300

7 Al-Maliki W A K, Alobaid F, Starkloff R, Kez V, Epple B. Investigation on the dynamic behaviour of a parabolic trough power plant during strongly cloudy days. Applied Thermal Engineering, 2016, 99: 114–132

8 Salazar G A, Fraidenraich N, de Oliveira C A A, de Castro Vilela O, Hongn M, Gordon J M. Analytic modeling of parabolic trough solar thermal power plants. Energy, 2017, 138: 1148–1156

9 Li L, Sun J, Li Y. Prospective fully-coupled multi-level analytical methodology for concentrated solar power plants: general modelling. Applied Thermal Engineering, 2017, 118: 171–187

10 Li L, Li Y, Sun J. Prospective fully-coupled multi-level analytical methodology for concentrated solar power plants: applications. Applied Thermal Engineering, 2017, 118: 159–170

11 Li L, Sun J, Li Y. Thermal load and bending analysis of heat collection element of direct-steam-generation parabolic-trough solar power plant. Applied Thermal Engineering, 2017, 127: 1530–1542

12 Li L, Sun J, Li Y, He Y L, Xu H. Transient characteristics of a parabolic trough direct-steam-generation process. Renewable Energy, 2019, 135: 800–810

13 Abutayeh M, Alazzam A, El-Khasawneh B. Balancing heat transfer fluid flow in solar fields. Solar Energy, 2014, 105: 381–389

14 Giostri A. Transient effects in linear concentrating solar thermal power plant. Dissertation for the Doctoral Degree. Italy: Politecnico Di Milano, 2014

15 Augsburger G, Favrat D. Modelling of the receiver transient flux distribution due to cloud passages on a solar tower thermal power plant. Solar Energy, 2013, 87: 42–52

16 Colmenar-Santos A, Munuera-Pérez F J, Tawfik M, Castro-Gil M. A simple method for studying the effect of scattering of the performance parameters of Parabolic Trough Collectors on the control of a solar field. Solar Energy, 2014, 99: 215–230

17 Noureldin K, Hirsch T, Pitz-Paal R. Virtual Solar Field-Validation of a detailed transient simulation tool for line focus STE fields with single phase heat transfer fluid. Solar Energy, 2017, 146: 131–140

18 Ma L, Xu E, Li J, Xu L, Li X. Analysis and validation of a thermal hydraulic dynamic model for the parabolic trough solar field. Energy, 2018, 156: 430–443

19 Xu E, Zhao D, Xu H, Li S, Zhang Z, Wang Z, Wang Z. The Badaling 1 MW parabolic trough solar thermal power pilot plant. Energy Procedia, 2015, 69: 1471–1478

20 Burkholder F, Kutscher C. Heat loss testing of Schott’s 2008 PTR70 parabolic trough receiver. Technical report NREL/TP-550–45633, 2009

21 Forristall R. Heat transfer analysis and modeling of a parabolic trough solar receiver implemented in engineering equation solver. Technical report NREL/TP-550–34169, 2003

22 Bellos E, Tzivanidis C. A detailed exergetic analysis of parabolic trough collectors. Energy Conversion and Management, 2017, 149: 275–292

23 Cao E. Heat Transfer in Process Engineering. McGraw-Hill Education, 2009

24 Strang G. Introduction to Applied Mathematics. Wellesley, MA: Wellesley-Cambridge Press, 1986

25 Jiang Y. Adjustability and stability of hydraulic network. Heating Ventilating & Air Conditioning, 1997, 27(3): 1–7 (in Chinese)

26 Chaudhry M H. Applied Hydraulic Transients (No. 627 C4). New York: Van Nostrand Reinhold, 1979

27 Arias D A, Gavilán A, Muren R. Pumping power parasitics in parabolic trough solar fields. In: Proceedings of the 15th International SolarPACES Symposium, Berlin, Germany, 2009

28 Munson Bruce R, Young D F, Okiishi T H. Fundamentals of Fluid Mechanics. New York: Wiley, 1990

29 Skousen P L. Valve Handbook. 2nd ed. McGraw-Hill Professional Publishing, 2004

30 Balmer R T. Modern Engineering Thermodynamics—Textbook with Tables Booklet. Academin Press, 2011

31 Petela R. Exergy of undiluted thermal radiation. Solar Energy, 2003, 74(6): 469–488

32 Ricardo V P. Simplified methodology for designing parabolic trough solar power plants. Dissertation for Doctoral Degree. Florida: University of South Florida, 2011

33 Geyer M, Lüpfert E, Osuna R, Esteban A. Eurotrough-parabolic trough collector developed for cost efficient solar power generation. In: 11th SolarPACES International Symposium on Concentrating Solar Power and Chemical Energy Technologies, Zurich, Switzerland, 2002

34 Martínez-Chico M, Batlles F J, Bosch J L. Cloud classification in a mediterranean location using radiation data and sky images. Energy, 2011, 36(7): 4055–4062