0
Research Papers

Experiments on Natural Convective Solar Thermal Achieved by Supercritical CO2/Dimethyl Ether Mixture Fluid

[+] Author and Article Information
Lin Chen

Department of Energy and
Resources Engineering,
College of Engineering,
Peking University,
Beijing 100871, China

Xin-Rong Zhang

Department of Energy and
Resources Engineering,
College of Engineering,
Peking University,
Beijing 100871, China
Beijing Key Laboratory for Solid Waste
Utilization and Management,
Peking University,
Beijing 100871, China
e-mail: zhxrduph@yahoo.com

1Corresponding author.

Contributed by the Solar Energy Division of ASME for publication in the JOURNAL OF SOLAR ENERGY ENGINEERING. Manuscript received October 15, 2012; final manuscript received January 17, 2014; published online March 6, 2014. Editor: Gilles Flamant.

J. Sol. Energy Eng 136(3), 031011 (Mar 06, 2014) (11 pages) Paper No: SOL-12-1283; doi: 10.1115/1.4026920 History: Received October 15, 2012; Revised January 17, 2014

The current study proposed an experimental investigation into the basic characteristics of solar thermal conversion using supercritical CO2–dimethyl ether (DME) natural convection. The main goals are to reduce the operation pressure while maintaining relative high solar thermal conversion efficiency. Experimental systems were established and tested in Shaoxing area (around N 30.0 deg, E 120.6 deg) of Zhejiang Province, China. Due to the preferable properties of supercritical fluids, very high Reynolds number natural convective flow can be achieved. Typical summer day results are presented and analyzed into detail in this paper. It is found that the introduction of DME has successfully reduced the operation pressure and the increase in DME fraction leads to further reduction. Different from pure supercritical CO2 systems, the collector pressure follows the trend of solar radiation with its peak value at noon, instead of continuously increasing mode. The mass flow rate and temperature are typically more stable and also more sensitive than pure supercritical CO2 tests due to the moderation of supercritical fluid properties when DME is introduced. At the same time, the averaged collector efficiency is less affected by the DME mass addition. It is also found that there possibly exist some optimal of DME mass fraction when both the system suitability and stable natural circulation can be achieved.

FIGURES IN THIS ARTICLE
<>
Copyright © 2014 by ASME
Your Session has timed out. Please sign back in to continue.

References

Davidson, J. H., Mantell, S. C., and Jorgensen, G., 2002, “Status of the Development of Polymeric Solar Water Heating System,” Adv. Sol. Energy, 15, pp. 149–186.
Langniss, O., and Ince, D., 2004, “Solar Water Heating: A Viable Industry in Developing Countries,” Refocus, 5(3), pp. 18–21. [CrossRef]
Liu, L., Wang, Z., Zhang, H., and Xue, Y., 2010, “Solar Energy Development in China—A Review,” Renewable Sustainable Energy Rev., 14(1), pp. 301–311. [CrossRef]
Jaisankar, S., Ananth, J., Thulasi, S., Jayasuthakar, S. T., and Sheeba, K. N., 2011, “A Comprehensive Review on Solar Water Heaters,” Renewable Sustainable Energy Rev., 15(6), pp. 3045–3050. [CrossRef]
Kalogirou, S. A., 2004, “Solar Thermal Collectors and Applications,” Prog. Energy Combust. Sci., 30(3), pp. 231–295. [CrossRef]
Chen, L., and Zhang, X. R., 2014, “Experimental Analysis on a Novel Solar Collector System Achieved by Supercritical CO2 Natural Convection,” Energy Convers. Manage., 77, pp. 173–182. [CrossRef]
Zhang, X. R., Zhang, Y. L., and Chen, L., 2014, “Experimental Study on Solar Thermal Conversion Based on Supercritical Natural Convection,” Renewable Energy, 62, pp. 610–618. [CrossRef]
Yamaguchi, H., Sawada, N., Suzuki, H., Ueda, H., and Zhang, X. R., 2010, “Preliminary Study on a Solar Water Heater Using Supercritical Carbon Dioxide as Working Fluid,” ASME J. Sol. Energy Eng., 132(1), pp. 101–106. [CrossRef]
Chen, L., Deng, B. L., and Zhang, X. R., 2013, “Experimental Study of Trans-Critical and Supercritical CO2 Natural Circulation Flow in a Closed Loop,” Appl. Therm. Eng., 59(1–2), pp. 1–13. [CrossRef]
Chen, L., Zhang, X. R., and Jiang, B., 2014, “Effects of Heater Orientations on the Natural Circulation and Heat Transfer in a Supercritical CO2 Rectangular Loop,” ASME J. Heat Transfer (in press) [CrossRef].
Chen, L., Zhang, X. R., Deng, B. L., and Jiang, B., 2013, “Effects of Inclination Angle and Operation Parameters on Supercritical CO2 Natural Circulation Loop,” Nucl. Eng. Des., 265, pp. 895–908. [CrossRef]
Budihardjo, I., and Morrison, G. L., 2009, “Performance of Water-in-Glass Evacuated Tube Solar Water Heaters,” Sol. Energy, 83(1), pp. 49–56. [CrossRef]
Dubey, S., and Tiwari, G. N., 2008, “Thermal Modeling of a Combined System of Photovoltaic Thermal (PV/T) Solar Water Heater,” Sol. Energy, 82(7), pp. 602–612. [CrossRef]
Morrison, G. L., Budihardjo, I., and Behnia, M., 2004, “Water-in-Glass Evacuated Tube Solar Water Heaters,” Sol. Energy, 76(1–3), pp. 135–140. [CrossRef]
Dahl, S. D., and Davidson, J. H., 1997, “Performance and Modeling of Thermosyphon Heat Exchangers for Solar Water Heaters,” ASME J. Sol. Energy Eng., 119(3), pp. 193–200. [CrossRef]
Mason, A. A., and Davidson, J. H., 1999, “Measured Performance and Modeling of an Evacuated-Tube, Integral-Collector-Storage Solar Water Heater,” ASME J. Sol. Energy Eng., 117(3), pp. 221–228. [CrossRef]
Alkhamis, A. I., and Sherif, S. A., 1997, “Feasibility Study of a Solar-Assisted Heating/Cooling System for an Aquatic Centre in Hot and Humid Climate,” Int. J. Energy Res., 21(9), pp. 823–839. [CrossRef]
Zhang, X. R., and Yamaguchi, H., 2008, “An Experimental Study on Evacuated Tube Solar Collector Using Supercritical CO2,” Appl. Therm. Eng., 28(10), pp. 1225–1233. [CrossRef]
Zhang, X. R., 2013, “A Preliminary Experimental Investigation on Characteristics of Natural Convection Based on Solar Thermal Collection Using Supercritical Carbon Dioxide,” Int. J. Energy Res., 37(11), pp. 1349–1360. [CrossRef]
Chen, L., Zhang, X. R., Okajima, J., and Maruyama, S., 2013, “Thermal Relaxation and Critical Instability of Near-Critical Fluid Microchannel Flow,” Phys. Rev. E, 87(4), p. 043016. [CrossRef]
Chen, L., Zhang, X. R., Okajima, J., and Maruyama, S., 2014, “Abnormal Microchannel Convective Fluid Flow Near the Gas-Liquid Critical Point,” Phys. A, 398, pp. 10–24. [CrossRef]
Chen, L., Deng, B. L., Jiang, B., and Zhang, X. R., 2013, “Thermal and Hydrodynamic Characteristics of Supercritical CO2 Natural Circulation in Closed Loops,” Nucl. Eng. Des., 257, pp. 21–30. [CrossRef]
Zhang, X. R., Chen, L., and Yamaguchi, H., 2010, “Natural Convective Flow and Heat Transfer of Supercritical CO2 in a Rectangular Circulation Loop,” Int. J. Heat Mass Transfer, 53(19–20), pp. 4112–4122. [CrossRef]
Hasan, M. M., Afroz, A. M., and Tsubaki, K., 2008, “Heat Transfer Coefficients and Pressure Drops During In-Tube Condensation of CO2/DME Mixture Refrigerant,” Int. J. Refrig., 31(8), pp. 1458–1466. [CrossRef]
Koyama, S., Takato, N., Kuwahara, K., Jin, D., Xue, J., and Miyara, A., 2006, “Experimental Study on the Performance of a Refrigerant Mixture CO2/DME System,” JSRAE Annual Conference, Kyushu, Japan, October 22–26, pp. 133–136 (in Japanese).
Onaka, Y., Miyara, A., Tsubaki, K., and Koyama, S., 2007, “Performance Analysis on Heat Pump Cycle of CO2/DME Mixture Refrigerant,” JSRAE Annual Conference, Tokyo, October 22–24, pp. 333–336 (in Japanese).
Chen, L., Zhang, X. R., Yamaguchi, H., and Liu, Z. S., 2010, “Effect of Heat Transfer on the Instabilities and Transitions of Supercritical CO2 Flow in a Natural Circulation Loop,” Int. J. Heat Mass Transfer, 53(19–20), pp. 4101–4111. [CrossRef]
Chen, L., Zhang, X. R., Cao, S., and Bai, H., 2012, “Study of Trans-Critical CO2 Natural Convection Flow With Unsteady Heat Input and Its Implications on System Control,” Int. J. Heat Mass Transfer, 55(23–24), pp. 7119–7132. [CrossRef]
Zhang, X. R., Yamaguchi, H., Fujima, K., Enomoto, M., and Sawada, N., 2005, “A Feasibility Study of CO2-Based Rankine Cycle Powered by Solar Energy,” JSME Int. J., Ser. B, 48(3), pp. 540–547. [CrossRef]
Zhang, X. R., Yamaguchi, H., Uneno, D., Fujima, K., Enomoto, M., and Sawada, N., 2006, “Analysis of a Novel Solar Energy Powered Rankine Cycle for Combined Power and Heat Generation Using Supercritical Carbon Dioxide,” Renewable Energy, 31(12), pp. 1839–1854. [CrossRef]
Zhang, X. R., Yamaguchi, H., and Uneno, D., 2007, “Experimental Study on the Performance of Solar Rankine System Using Supercritical CO2,” Renewable Energy, 32(15), pp. 2617–2628. [CrossRef]
Zhang, X. R., and Yamaguchi, H., 2007, “Forced Convection Heat Transfer of Supercritical Carbon Dioxide in a Horizontal Circular Tube,” J. Supercrit. Fluids, 41(3), pp. 412–420. [CrossRef]
Chen, L., and Zhang, X. R., 2014, “Heat Transfer and Various Convection Structures of Near-Critical CO2 Flow in Microchannels,” Appl. Therm. Eng. (in press). [CrossRef]
Chen, L., and Zhang, X. R., 2011, “Simulation of Heat Transfer and System Behavior in a Supercritical CO2 Based Thermosyphon: Effect of Pipe Diameter,” ASME J. Heat Transfer, 133(12), p. 122505. [CrossRef]

Figures

Grahic Jump Location
Fig. 1

Variation of thermophysical properties of the CO2–DME mixture refrigerant with different DME mass fractions at 8.0 MPa. (a) Density; (b) specific heat; (c) thermal conductivity; and (d)viscosity.

Grahic Jump Location
Fig. 2

Schematic diagram of the supercritical CO2–DME natural convection based solar water heater

Grahic Jump Location
Fig. 3

Variations of the measured solar radiation and fluid pressures with test time. The mass fraction of DME is 10%. (a) July 8, 2010 and (b) Aug. 9, 2010.

Grahic Jump Location
Fig. 4

Variations of the measured solar radiation and mass flow rate with the test time. The mass fraction of DME is 10%. (a) July 8, 2010 and (b) Aug. 9, 2010.

Grahic Jump Location
Fig. 5

Variations of the measured mass flow rate and fluid temperatures with the test time. The mass fraction of DME is 10%. (a) July 8, 2010 and (b) Aug. 9, 2010.

Grahic Jump Location
Fig. 6

Variations of the collector efficiency with the comprehensive coefficient. The mass fraction of DME is 10%. (a) July 8, 2010 and (b) Aug. 9, 2010.

Grahic Jump Location
Fig. 7

Variations of the measured solar radiation and fluid pressures with the test time. The mass fraction of DME is 20%. (a) Sept. 8, 2010 and (b) Sept. 12, 2010.

Grahic Jump Location
Fig. 8

Variations of the measured solar radiation and mass flow rate with the test time. The mass fraction of DME is 20%. (a) Sept. 8, 2010 and (b) Sept. 12, 2010.

Grahic Jump Location
Fig. 9

Variations of the measured mass flow rate and fluid temperatures with the test time. The mass fraction of DME is 20%. (a) Sept. 8, 2010 and (b) Sept. 12, 2010.

Grahic Jump Location
Fig. 10

Variations of the collector efficiency with the comprehensive coefficient. The mass fraction of DME is 20%. (a) Sept. 8, 2010 and (b) Sept. 12, 2010.

Grahic Jump Location
Fig. 11

Variations of the time-averaged pressures with the mass fraction of DME

Grahic Jump Location
Fig. 12

Variations of the measured collector efficiency with the comprehensive coefficient under three different mass fractions of DME, 0%, 10%, and 20%. Every point shown in this figure represents a time-averaged value during one day.

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In