Research Papers

Numerical Simulation of Saturated Flow Boiling Heat Transfer of Ammonia/Water Mixture in Bubble Pumps for Absorption–Diffusion Refrigerators

[+] Author and Article Information
Soo W. Jo

e-mail: soowjo@gmail.com

W. E. Lear

Department of Mechanical and
Aerospace Engineering,
University of Florida,
MAE-A Building: 231 MAE-A Building,
P.O. Box 116250,
Gainesville, FL 32611-6250

1Corresponding author.

2Present address: Samsungtechwin R&D Center, Power Systems Division, 701 Sampyeong-dong, Bundang-gu, Seongnam, Gyeonggi-do 463-400, Republic of Korea.

Manuscript received April 11, 2013; final manuscript received July 21, 2013; published online October 21, 2013. Assoc. Editor: Zahid Ayub.

J. Thermal Sci. Eng. Appl 6(1), 011007 (Oct 21, 2013) (9 pages) Paper No: TSEA-13-1067; doi: 10.1115/1.4025091 History: Received April 11, 2013; Revised July 21, 2013

This paper addresses a multidimensional numerical simulation of the saturated flow boiling heat transfer in bubble pumps of absorption–diffusion refrigeration cycles. The bubble pump with a shape of vertical tube is subjected to a uniform heat flux from the tube outer wall surface along the entire pump length. As the bubble pump wall is heated, a nonazeotropic mixture of saturated strong ammonia/water entering into the bubble pump transforms to ammonia vapor and diluted ammonia/water mixture. The weaker ammonia/water mixture is lifted by the buoyant force created by the ammonia vapor. The present multidimensional numerical simulation was performed using the two-fluid model with the equilibrium phase change model and the standard k-ε turbulence model. The numerical model designed for the present simulation was validated through a comparative study referring to available experimental data. The present numerical model was compared with the one-dimensional model to assess its applicability for numerical simulation of the saturated flow boiling heat transfer in bubble pumps. As a result, it is seen that the present numerical model predicts the performance of ammonia/water bubble pumps more realistically than the one-dimensional model. In addition, the effects of the bubble pump's geometrical dimension and heat input on the pump performance were investigated using the present numerical approach.

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Wang, X. X., and Chua, H. T., 2009, “Absorption Cooling: A Review of Lithium Bromide-Water Chiller Technologies,” Recent Pat. Mech. Eng., 2(3), pp. 193–213. [CrossRef]
Srikhirin, P., Aphornratana, S., and Chungpaibulpatana, S., 2001, “A Review of Absorption Refrigeration Technologies,” Renewable Sustainable Energy Rev., 5(4), pp. 343–372. [CrossRef]
Dannen, G., 1997, “The Einstein-Szilárd Refrigerators,” Sci. Am., 276(1), pp. 90–95. [CrossRef]
White, S. J., 2001, “Bubble Pump Design and Performance,” M.S. thesis, Georgia Institute of Technology, Atlanta, GA.
De Cachard, F., and Delhaye, J., 1996, “A Slug-Churn Flow Model for Small-Diameter Airlift Pumps,” Int. J. Multiphase Flow, 22(4), pp. 627–649. [CrossRef]
Shelton, S. V., Stewart, S. W., and Erickson, D., 2002, “Bubble Pump Design for Single Pressure Absorption Refrigeration Cycles,” ASHRAE Trans., 108(1), pp. 867–876.
Koyfman, A., Jelinek, M., and Levy, A., 2003, “An Experimental Investigation of Bubble Pump Performance for Diffusion Absorption Refrigeration System With Organic Working Fluids,” Appl. Therm. Eng., 23(15), pp. 1881–1894. [CrossRef]
Sathe, A., 2001, “Experimental and Theoretical Studies on a Bubble Pump for a Diffusion Absorption Refrigeration System,” M.S. thesis, India Institute of Technology, Madras, India.
Dammak, N., Chaouachi, B., and Gabsi, S., 2010, “Optimization of the Geometrical Parameters of a Solar Bubble Pump for Absorption-Diffusion Cooling Systems,” Am. J. Eng. Appl. Sci., 3(4), pp. 693–698. [CrossRef]
Benhmidene, A., Chaouachi, B., and Gabsi, S., 2011, “Modelling of Heat Flux Received by a Bubble Pump of Absorption-Diffusion Refrigeration Cycles,” Heat Mass Transfer, 47(11), pp. 1–7. [CrossRef]
Benhmidene, A., Chaouachi, B., and Bourouis, M., 2011, “Numerical Prediction of Flow Patterns in Bubble Pumps,” ASME J. Fluids Eng., 133(3), p. 031302-1–7. [CrossRef]
ansys, 2011, ANSYS-CFX User Manual, ANSYS, Inc., Canonsburg, PA.
Daewan, A., 2011, Tackling Turbulent Flows in Engineering, Springer-Verlag, New York.
Lai, J., and Farouk, B., 1993, “Numerical Simulation of Subcooled Boiling and Heat Transfer in Vertical Ducts,” Int. J. Heat Mass Transfer, 36(6), pp. 1541–1551. [CrossRef]
Wintterle, T., 2004, “Development of a Numerical Boundary Condition for the Simulation of Nucleate Boiling at Heated Walls,” Diploma thesis, University of Stuttgart, Stuttgart, Germany.
NIST, 2010, REFPROP User Manual, National Institute of Standards and Technology, Gaithersburg, MD.
ASHRAE, 2009, Handbook: Fundamentals, American Society of Heating, Refrigerating and Air-Conditioning Engineers, Atlanta, GA.
ansys, 2009, Multiphase Flow Modeling in ANSYS CFX, Training Manual for ANSYS CFX, ANSYS, Inc., Canonsburg, PA.
Krepper, E., Koncar, B., and Egorov, Y., 2007, “CFD Modelling of Subcooled Boiling-Concept, Validation and Application to Fuel Assembly Design,” Nucl. Eng. Des., 237(7), pp. 716–731. [CrossRef]
Bartolomei, G., and Chanturiya, V., 1967, “Experimental Study of True Void Fraction When Boiling Subcooled Water in Vertical Tubes,” Therm. Eng., 14(2), pp. 123–128.
Nakla, M. E., Groeneveld, D., and Cheng, S., 2011, “Experimental Study of Inverted Annular Film Boiling in a Vertical Tube Cooled by R-134a,” Int. J. Multiphase Flow, 37(1), pp. 67–75. [CrossRef]


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Fig. 1

Schematic of an absorption–diffusion refrigerator with a bubble pump

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Fig. 2

Schematic of the simplified simulation model

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Fig. 3

Isometric mesh views of pumps A and D

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Fig. 12

Comparisons of void fraction in the pump A between the present model and the 1D model [11]

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Fig. 13

Comparisons of void fraction in the pump D between the present model and the 1D model [11]

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Fig. 14

Void fraction profiles for pump D

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Fig. 11

Void fractions in pump D (Enlarged in the radial direction, the right side of each drawing is the pump wall)

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Fig. 10

Liquid and vapor velocity vectors in pump D subjected to qw =  25 kW/m2 (The right side of each drawing is the pump wall)

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Fig. 9

Liquid and vapor velocity contours in pump D (Enlarged in the radial direction, the right side of each drawing is the pump wall)

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Fig. 8

Comparison between the predicted and measured liquid temperature profiles at 0.82 m height

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Fig. 7

Comparison between the predicted and measured void fraction profiles

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Fig. 6

Discretized solution domain with a fine grid in the near-wall region

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Fig. 5

Comparison of vapor and liquid velocities between the original and finer meshes

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Fig. 4

Comparison of void fraction between the original mesh and the finer mesh

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Fig. 15

Comparison of pumping ratio at the pump outlet between the present model and the 1D model [11]

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Fig. 16

Slip ratio for pump A

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Fig. 17

Slip ratio for pump D




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