Modeling the performance of a two-bed solar adsorption chiller using a multi-walled carbon nanotube/MIL-100(Fe) composite adsorbent

- Conventional two-bed adsorption chillers use silica-gels or zeolites as adsorbents.
- These conventional chillers fail to satisfy household/commercial refrigeration needs.
- Adsorption chillers with MOFs as adsorbents are expected to show better performance.
- MWCNTs are nanomaterials with high thermal conductivities and structural perfection.
- A MWCNT/MOF composite adsorbent has been proposed for solar adsorption chillers.

Adsorption-based cooling systems are becoming increasingly popular due to a continuous rise in the worldwide demand for refrigeration and air-conditioning. This study aims to enhance the cooling performance of a solar-powered adsorption chiller using a novel multi-walled carbon nanotube (MWCNT)/MIL-100(Fe) composite adsorbent. A numerically validated modeling approach has been employed to evaluate the coefficient of performance (COP) and specific cooling power (SCP) for the two-bed adsorption chiller. For solar energy input, a flat-plate solar collector has been employed with three different configurations of glaze - (a) single-glazed cover, (b) double-glazed cover, and (c) single-glazed cover with transparent insulation material. It has been observed that the MWCNT/MIL-100(Fe) composite adsorbent containing 6.1% MWCNTs results in a maximum achievable cooling power of 455 Wkg−1for the adsorption chiller. The proposed MWCNT/MIL-100(Fe) composite adsorbent can be considered as a successful potential replacement of the traditionally used silica gel- and zeolite-based adsorbents for use in the next generation of high-performance solar adsorption chillers.