TY - JOUR
T1 - Compact heat exchanger designs for difluoromethane-activated carbon composites based adsorption cooling systems
AU - Yagnamurthy, Sai
AU - Rakshit, Dibakar
AU - Jain, Sanjeev
AU - Saha, Bidyut Baran
N1 - Publisher Copyright:
© 2022
PY - 2023/1
Y1 - 2023/1
N2 - To further the deployment of adsorption cooling systems for various applications, the cooling potential assessment of novel activated carbon-based pairs with R32 refrigerant is carried out in this work. The compositions of Maxsorb-III activated carbon with H25 Graphene nanoplatelets (GNP), 1-Hexyl-3-methylimidazolium bis(trifluormethylsulfonyl)imide ([HMIM][Tf2N]) ionic liquid, and polyvinyl alcohol (PVA), that have yielded the highest volumetric cooling energy (80:0:10:10) and thermal conductivity (40:40:10:10) respectively are considered for performance evaluation. The present study focuses on the under-explored aspect of heat exchanger optimization for HFC-based adsorbents through numerical analysis of two finned tube heat exchanger design configurations, viz., annular and longitudinal. A computationally less expensive numerical modeling is adopted, enabled by a scaling analysis. The impact of fin aspect ratios is analyzed for the composites with both the finned tube design configurations, and the significance of the adsorbent's thermal conductivity in realizing compact lightweight heat exchangers is highlighted. Further, an impact assessment of the adsorbent's orientation within the heat exchanger is presented for its anisotropic thermal conductivity characteristics. While it is observed that the annular fin configuration yields higher cooling performance for the composition 80:0:10:10, the longitudinal fin configuration yields a higher coefficient of performance for the composition 40:40:10:10 with a minimal decrement in the volumetric cooling power (<4.9%) over the annular fin configuration. The higher thermal conductivity of the composition 40:40:10:10 is seen to yield savings in the heat exchanger mass of up to 40.9% over that of the composition 80:0:10:10, for the same cooling capacity. The results indicate that present working pairs offer better cooling capacities and compact designs over other HFC-based studies in the literature.
AB - To further the deployment of adsorption cooling systems for various applications, the cooling potential assessment of novel activated carbon-based pairs with R32 refrigerant is carried out in this work. The compositions of Maxsorb-III activated carbon with H25 Graphene nanoplatelets (GNP), 1-Hexyl-3-methylimidazolium bis(trifluormethylsulfonyl)imide ([HMIM][Tf2N]) ionic liquid, and polyvinyl alcohol (PVA), that have yielded the highest volumetric cooling energy (80:0:10:10) and thermal conductivity (40:40:10:10) respectively are considered for performance evaluation. The present study focuses on the under-explored aspect of heat exchanger optimization for HFC-based adsorbents through numerical analysis of two finned tube heat exchanger design configurations, viz., annular and longitudinal. A computationally less expensive numerical modeling is adopted, enabled by a scaling analysis. The impact of fin aspect ratios is analyzed for the composites with both the finned tube design configurations, and the significance of the adsorbent's thermal conductivity in realizing compact lightweight heat exchangers is highlighted. Further, an impact assessment of the adsorbent's orientation within the heat exchanger is presented for its anisotropic thermal conductivity characteristics. While it is observed that the annular fin configuration yields higher cooling performance for the composition 80:0:10:10, the longitudinal fin configuration yields a higher coefficient of performance for the composition 40:40:10:10 with a minimal decrement in the volumetric cooling power (<4.9%) over the annular fin configuration. The higher thermal conductivity of the composition 40:40:10:10 is seen to yield savings in the heat exchanger mass of up to 40.9% over that of the composition 80:0:10:10, for the same cooling capacity. The results indicate that present working pairs offer better cooling capacities and compact designs over other HFC-based studies in the literature.
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U2 - 10.1016/j.icheatmasstransfer.2022.106549
DO - 10.1016/j.icheatmasstransfer.2022.106549
M3 - Article
AN - SCOPUS:85143871566
SN - 0735-1933
VL - 140
JO - International Communications in Heat and Mass Transfer
JF - International Communications in Heat and Mass Transfer
M1 - 106549
ER -