THERMODYNAMIC ANALYSIS OF HEAT AND MASS TRANSFER ENHANCEMENT FOR R134a-DMAC/CNT VAPOUR ABSORPTION REFRIGERATION SYSTEM

摘要

The objective of this paper is to study thermodynamic analysis of R134a-DMAC and R134a-DMAC/CNT vapour absorption system and compare this both system performance. This investigation for R134a-DMAC is carried out based on the correlations available in the literature. The change of thermophysical properties for R134a-DMAC/CNT is predicted and is incorporated in the pure R134a-DMAC correlations. The analysis is carried for 1 kW evaporator capacity and effectiveness of solution heat exchanger is taken as 0.8. Variations in the performance parameters of the system with and without nano fluids are studied against various operating temperatures of generator, absorber and different volume concentration. The result of this theoretical study shows that co-efficient of performance (COP) of system with CNT nano fluid is improved as well as the absorber capacity also increased due to enhanced heat transfer of nano fluids. It also observed that the performance achieved by the pure R134a-DMAC at the elevated generator temperature could be achieved at low generator temperature using R134a-DMAC/CNT.