Figure 11 Required reduction of VCAS cooling capacity in all three modes
Figure 11 describes the required reduction in the cooling capacity of a vapor compression air conditioner when it is operated in mode 1, mode 2, and mode 3. In mode 1 when the supply air condition is given as 27.5°C and 60% Relative Humidity, the phenomenal reduction in the average cooling capacities of vapor compression air conditioners are 73%, 70%, and 68% respectively at the ambient humidity ratios of 21,22 and 28 gkg-1d.a. At mode 2 when the supply of air conditioning is set as 22.5°C and 75% Relative Humidity, the significant reduction in the average cooling capacities of vapor compression air conditioners are 57%, 56.5%, and 57.5% respectively at the same ambient humidity ratios tested for mode 1.
Similarly in mode 3, when the supply air condition is 22°C and 50% Relative Humidity, the substantial reduction in the average cooling capacities for the vapor compression air conditioners are 34%, 35%, and 41% respectively. This is for the same ambient humidity ratios tested for mode 1 and mode 2.
Though the supply air conditioning for mode 1 and mode 2 are not exactly in the comfort zone, the cooling provided in mode 1 and mode 2 is significant and the supply air conditioning is only marginally away from the comfort zone. Therefore, the solid desiccant-vapor compression air conditioner hybrid cooling system delivers an average reduction in cooling capacities of 70.5% and 57% in mode 1 and mode 2 respectively. This demonstrates the energy-efficient working of the HSDVC in hot-humid climates. The supply of air conditioning in mode 3 is exactly in the comfort zone. In mode 3, the hybrid cooling system gives an average reduction in the cooling capacity of the vapor compression air conditioner by 37%. From the results of the study of the hybrid cooling system, it is found that the hybrid cooling system could significantly induce a reduction in the cooling capacity of the vapor compression air conditioner from 37% to 71%.
Conclusion
A single-stage solid desiccant cooling system is simulated by using a BLUEJ programming framework. The system is tested for numerous hot-humid ambient conditions. The results of the simulation of the solid desiccant cooling system are given as an input entry air condition for the vapor compression air conditioning system. The system is made to work in three modes namely 1, 2, and 3. The results of the study reveal that the system could potentially provide a reduction in the cooling capacity of the vapor compression air conditioner under the operations of mode 1, mode 2, and mode 3. The average reduction in the cooling capacity of the vapor compression air conditioner for the three modes is 71%, 57%, and 37% respectively. The solid desiccant cooling system could potentially serve as a pre-cooler to work along with the air conditioning unit in a hybrid cooling mode. Due to the substantial cooling capacity reductions demonstrated by the hybrid cooling system, the solid desiccant cooling system could be used as a pre-cooler coupled with an air conditioning system leading the path to energy efficiency
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest concerning the research, authorship, and/or publication of this article.
Acknowledgment
This project is carried out by the funding provided by DST-SERI, India, and the file no is DST/ TM/SERI/2k12/81(G). The authors thank the funding agency, which helped to establish the “Centre For Alternate Cooling” at PSG College of Technology, where this work is being carried out. The authors also acknowledge the funding provided by the industry partner, Trident Pneumatics Pvt Ltd, Coimbatore, India for their support rendered in the co-sponsoring and the guidance for the project.
References
  1. Fadnavis S, Mahajan AS, Choudhury AD, Roy C, Singh M, Biswas MS, Pandithurai G, Prabhakaran T, Lal S, Venkatraman C & Ganguly D 2020, ’Atmospheric aerosols and trace gases. In Assessment of Climate Change over the Indian Region’, pp. 93-116, Springer, Singapore.
  2. Biardeau, LT, Davis, LW, Gertler, P, & Wolfram, C 2020, ’Heat exposure and global air conditioning’, Nature Sustainability, vol. 3, no. 1, pp. 25–28.
  3. Birol, F 2018, ’The Future of Cooling: Opportunities for energy-efficient air conditioning, The Future of Cooling: Opportunities for energy-efficient air conditioning, International Energy Agency
  4. Renaldi, R, Miranda, ND, Khosla, R & McCulloch, MD 2021, ’Patent landscape of not-in-kind active cooling technologies between 1998 and 2017’, Journal of Cleaner Production, vol. 296, Article No: 126507.
  5. Liu, H, Dai, YJ, Köhler, M, & Wang, RZ 2013, ’Simulation and parameter analysis of a two-stage desiccant cooling/heating system driven by solar air collectors’, Energy Conversion and Management, vol. 67, pp. 309–317
  6. Kabeel, AE & Bassuoni, MM 2013, ’Feasibility study and life cycle assessment of two air dehumidification systems’, Global Advanced Research Journal of Physical and Applied Sciences, vol. 2, no. 1, pp. 8–16.
  7. Jani, DB, Mishra, M & Sahoo, PK 2016, ’Performance prediction of solid desiccant - Vapor compression hybrid air-conditioning system using artificial neural network’, Energy, vol. 103, pp. 618–629.
  8. Jani, DB, Mishra, M & Sahoo, PK 2018, ’Solar Assisted Solid Desiccant—Vapor Compression Hybrid Air-Conditioning System’, Energy, Environment, and Sustainability, pp. 233–250.
  9. Jia, CX, Dai, YJ, Wu, JY & Wang, RZ 2006, ’Analysis on a hybrid desiccant air-conditioning system’, Applied Thermal Engineering, vol. 26, no. 17–18, pp. 2393–2400.
  10. Hussain, S, Kalendar, A, Rafique, MZ & Oosthuizen, P 2020, ’Numerical investigations of solar-assisted hybrid desiccant evaporative cooling system for hot and humid climate’, Advances in Mechanical Engineering, vol. 12, no. 6, pp. 1–16.
  11. Ukai, M, Tanaka, Hiroaki, Tanaka, Hideki & Okumiya, M 2018, ’Performance analysis and evaluation of desiccant air-handling unit under various operation condition through measurement and simulation in hot and humid climate’, Energy and Buildings, vol. 172, pp. 478–492.
  12. Lee, Y, Park, S & Kang, S 2021, ’Performance analysis of a solid desiccant cooling system for a residential air conditioning system’, Applied Thermal Engineering, vol. 182, pp. 116091
  13. Sohani, A., Cornaro, C., Shahverdian, M.H., Moser, D., Pierro, M., Olabi, A.G., Karimi, N., Nižetić, S., Li, L.K. & Doranehgard, M.H., 2023. Techno-economic evaluation of a hybrid photovoltaic system with hot/cold water storage for poly-generation in a residential building. Applied Energy, 331, p.120391.
  14. Singh, G. and Das, R., 2023. Performance Analysis of Evaporation and Heat Wheel-Based Building Air Conditioning Systems. Journal of Energy Resources Technology, 145(3), p.032101.
  15. Luo, W.J., Faridah, D., Fasya, F.R., Chen, Y.S., Mulki, F.H. and Adilah, U.N., 2019. Performance enhancement of hybrid solid desiccant cooling systems by integrating solar water collectors in Taiwan. Energies, 12(18), p.3470.
  16. Worek, W.M. and Moon, C.J., 1988. Desiccant integrated hybrid vapor-compression cooling: performance sensitivity to outdoor conditions. Heat Recovery Systems and CHP, 8(6), pp.489-501.
  17. Liang, J.D., Kao, C.L., Tsai, L.K., Chiang, Y.C., Tsai, H.C. and Chen, S.L., 2022. Performance investigation of a hybrid ground-assisted desiccant cooling system. Energy Conversion and Management, 265, p.115765.
  18. Venkatesh, R, Ganesh, M, Suriyaprakash, S, Deva Surya, SE, Ashok Kumar, L & Rudramoorthy, R, 2021, ‘Experimental and simulation study of the performance of a desiccant loop cooling system’, Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy, vol.8, pp.1914-1932.