TY - JOUR
TI - Performance improvement of double-tube gas cooler in CO2 refrigeration system using nanofluids
AU - Sarkar Jahar
JN - Thermal Science
PY - 2015
VL - 19
IS - 1
SP - 109
EP - 118
PT - Article
AB - The theoretical analyses of the double-tube gas cooler in transcritical  carbon dioxide refrigeration cycle have been performed to study the  performance improvement of gas cooler as well as CO2 cycle using Al2O3, TiO2,  CuO and Cu nanofluids as coolants. Effects of various operating parameters  (nanofluid inlet temperature and mass flow rate, CO2 pressure and particle  volume fraction) are studied as well. Use of nanofluid as coolant in  double-tube gas cooler of CO2 cycle improves the gas cooler effectiveness,  cooling capacity and COP without penalty of pumping power. The CO2 cycle  yields best performance using Al2O3-H2O as a coolant in double-tube gas  cooler followed by TiO2-H2O, CuO-H2O and Cu-H2O. The maximum cooling COP  improvement of transcritical CO2 cycle for Al2O3-H2O is 25.4%, whereas that  for TiO2-H2O is 23.8%, for CuO-H2O is 20.2% and for Cu-H2O is 16.2% for the  given ranges of study. Study shows that the nanofluid may effectively use as  coolant in double-tube gas cooler to improve the performance of transcritical  CO2 refrigeration cycle.