This study investigates the performance attributes of a vapor compression refrigeration system (VCRS) with employing R134a/MWCNT-oil mixture and liquid-suction heat exchanger (LSHE) with/without twisted tape turbulator (TTT). The tests are done at different cycle pressure ratios (6.55-10.12), TTT twist ratios (1 ≤ λ ≤ 4), and nanoparticles’ mass concentrations (0 ≤ φ ≤ 0.5%). The experiments state that the exergy destruction rates are reduced by employing LSHE, TTT with reducing its twist ratio, and engaging R134a/MWCNT-oil mixture with increasing the MWCNTs loading, besides growing the cycle pressure ratio. Compared to the simple VCRS, the maximum enhancements in the COP and exergy efficiency (ηEx) of the VCRS are 37.3% and 126.5%, respectively, while compared to the simple LSHE, its effectiveness is improved by 97.9% obtained by simultaneously applying LSHE with TTT of λ = 1 and R134a/MWCNT-oil mixture of φ = 0.5%. Correlations are supplied to predict the COP and ηEx of the VCRS besides the effectiveness of LSHE. |
