Heat and Mass Transfer-Enhancement Technique Used for Vapour Absorption Refrigeration System

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.

Download Full-text

EFFECTS OF INSERTED POROUS SQUARE CYLINDER ON HEAT- AND MASS-TRANSFER ENHANCEMENT IN A CHANNEL

Computational Thermal Sciences An International Journal ◽

10.1615/computthermalscien.2018022498 ◽

2018 ◽

Vol 10 (5) ◽

pp. 405-420

Author(s):

H. Mahdhaoui ◽

Xavier Chesneau ◽

Ali Hatem Laatar

Keyword(s):

Mass Transfer ◽

Heat And Mass Transfer ◽

Square Cylinder ◽

Transfer Enhancement ◽

Mass Transfer Enhancement

Download Full-text

Review of Technology Used to Improve Heat and Mass Transfer Characteristics of Adsorption Refrigeration System

International Journal of Air-Conditioning and Refrigeration ◽

10.1142/s2010132516300032 ◽

2016 ◽

Vol 24 (02) ◽

pp. 1630003 ◽

Cited By ~ 8

Author(s):

Anirban Sur ◽

Randip K. Das

Keyword(s):

Mass Transfer ◽

Heat And Mass Transfer ◽

Waste Heat ◽

Transfer Characteristic ◽

Low Grade ◽

Transfer Performance ◽

Refrigeration System ◽

Adsorption Refrigeration ◽

System A ◽

Absorption Refrigeration System

Researchers proved that, heat powered adsorption refrigeration technology is very effective methods for reutilization of low-grade thermal energy such as industrial waste heat, solar energy, and exhaust gases from engines. But to make it commercially competitive with the well-known vapor compression and absorption refrigeration system, the processes require high rates of heat and mass transfer characteristic between adsorbate and adsorbent as well as externally supplied heat exchanging fluid. This paper reviews various techniques that have been developed and applied to enhance the heat transfer and mass transfer in adsorber beds, and also discuss their effects of the performance on adsorption system. A comprehensive literature review has been conducted and it was concluded that this technology, although attractive, has limitations regarding its heat and mass transfer performance that seem difficult to overcome. Therefore, more researches are required to improve heat and mass transfer performance and sustainability of basic adsorption cycles.

Download Full-text