Internal Power Recovery in Cryogenic Cooling Plants Part I: Expander Development

The amount of the electrical power required by refrigeration systems is relevant worldwide. It is evaluated in the order of 15% of the total electricity production taking refrigeration and air-conditioning into consideration. For this reason, in the last years several energy saving techniques have been proposed to reduce the power demand of such plants. The paper deals with the development of an innovative internal recovery system for cryogenic cooling plants. Such a system consists in a Compressor-Expander Group (CEG) designed on the basis of the automotive turbocharging technology. In particular, the paper is focused on the design of the expander, the critical component of the CEG system. Due to the low volumetric flow entering the expander and the high expansion ratio, a commercial turbocharger expander wheel was strongly modified. It was equipped with a transonic nozzle, designed to have a radially inflow full admission. To verify the performance of such a machine and suggest improvements, two different set of nozzles have been designed and modelled by means of the commercial Ansys-CFX software. steady-state 3D CFD simulations of the second-generation prototype are presented and compared with the initial ones.





References:
[1] S. Devotta, S. Sicars, IPCC/TEAP Special Report: Safeguarding the Ozone Layer and the Global Climate System, Chap. 4 – Refrigeration, Cambridge University Press, 2005.
[2] Arnemann M., Energy efficiency of refrigeration systems, International Refrigeration and Air Conditioning Conference, Paper 1356, 16-19 July 2012, West Lafayette (USA).
[3] Borlein C., Energy savings in commercial refrigeration equipment: Low pressure control, Schneider Electric White paper, August 2011.
[4] Yin X, Li S., Zheng Y., Cai W., Energy-saving-oriented control strategy for vapor compression refrigeration cycle systems, ICIEA 9th Conference on Industrial Electronics and Applications IEEE 2014.
[5] P. D. Gaspar, P. D. da Silva, Handbook of Research on Advances and Applications in Refrigeration Systems and Technologies, Engineering Science Reference, 2015.
[6] J. Sarkar, Ejector Enhanced Vapor Compression Refrigeration and Heat Pump Systems - A Review, Renewable and Sustainable Energy Reviews 16, 6647-6659; 2012
[7] Widell K.N., Eikevik T., Reducing power consumption in multi-compressor refrigeratopn systems, International Journal of refrigeration, Vol. 33, 88-94, 2010.
[8] Joost J. Brasz, Carrier Corporation, Refrigeration apparatus with expansion turbine, European patent EP 0 676 600 B1, September 6, 2000.
[9] F.L. Goldsberry, Refrigerant expander compressor, US Patent, 3 932 159, Jan 13, 1976.
[10] D.A. Ritchie, Energy covery system for refrigeration systems, US Patent, 4 141 222, Feb. 27, 1979.
[11] W.T. Osborne, Refrigeration system with turbine drive for compressor, US Patent 3 276 226, Oct. 4, 1966.
[12] B. Mitra, Y.H. Chen, Refrigerant vapor compression system with dual economizer circuits, International application published under the patent cooperation treaty (PCT), WO 2008/130359 A1, 30 Oct. 2008;
[13] B. Mitra, Y.H. Chen, Refrigerant vapor compressin system with flash tank economizer, International application published under the patent cooperation treaty (PCT), WO 2008/140454 A1, 20 Nov. 2008.
[14] F. T. Abdelmalek, Centrifugal gas compressor expander for refrigeration, US Patent 5 136 854, Aug 11, 1992.
[15] S. Ro, Refrigeration apparatus with turbo compressor, US Patent, 7 451 616, Nov. 18, 2008.
[16] T. J. Leck, D.B. Bivens, F. Zhao, M. Rohacek, Refrigeration/air conditioning apparatus powered by an engine exhaust gas driven turbine, US Patent, 2006/0242985 A1, Nov. 2, 2006.
[17] M. Ascani, Refrigerating Device and Method for Circulating a Refrigerating Fluid Associated with it, United States Patent; Patent No.: Us 8,505,317 B2; Aug.13, 2013.
[18] Cerri G., Alavi S. B., Chennaoui L., Giovannelli A., Mazzoni S., Optimum turbomachine selection for power regeneration in vapor compression cool production plants, International Journal of Mechanical, Aerospace, Industrial and Mechatronics Engineering Vol. 9, No. 4, 2015.
[19] Archilei E. M., Expander Compressor Goup for energy saving in cryogenic plants, Master Thesis, 2012.
[20] COLD-ENERGY Technical Report OR3-A3, Design, CEG prototype, Test bench, 2014.
[21] S.L. Dixon, CA. Hall, Fluid Mechanics and Thermodynamics of Turbomachinery, Butterworth Heinemann, Sixth Edition, 2010.
[22] O.E. Baljè, Turbomachines: A Guide to Design, Selection, and Theory, John Wiley and Sons, New York; 1980.
[23] NIST Reference Fluid Thermodynamic and Transport Properties – REFPROP Version 7.0.
[24] A. Giovannelli, E.M. Archilei, Design of an expander for internal power recovery in cryogenic cooling plants, Energy Procedia, Vol. 82; Dec 2015, pp. 180-185.
[25] Aungier R.H., A fast, accurate gas equation of state for fluid dynamic analysis applications, Journal of Fluid Engineering, Vol. 117, p. 277–281, 1995.