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Thermo-physical properties, heat transfer characteristics and performance of nano-enhanced refrigerants : a review

Bibin B. S., Chereches Elena Ionela, Mystkowski Arkadiusz, Śmierciew Kamil, Dudar Adam, Gundabattini Edison

Archives of Thermodynamics

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2024

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Vol. 45, no. 2

311--322

EN

To boost the efficacy of a refrigeration system, researchers have imported nanoparticles into refrigerants in recent years. This paper comprehensively reviewed the properties, heat transfer performance, and system performance of nano-added refrigerants in recent years. This article likewise assists with recognizing the gap in past research works and explores the possibilities for additional work. Refrigerant R134a charged with the nanoparticles TiO2 has the highest value of coefficient of performance which is 63.5% higher than that of Al2O3 nanoparticle charged R134a. Charging of the nano-refrigerants has enhanced the heat transfer performance of vapour compression refrigeration systems, particularly in the pool and nucleate boiling heat transfer. The heat transfer coefficient of R134a-based nano-refrigerant is enhanced by 42% and 30.2% with CuO and TiO2 nanoparticles respectively. The inclusions of nanomaterials, concerning their physical phenomena, influencing the vapour compression refrigeration system are confined in this paper.

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Predictive analysis on the influence of AL2o3 and CuO nanoparticles on the thermal conductivity of R1234yf-based refrigerants

Bibin Baiju S., Bhramara Panitapu, Mystkowski Arkadiusz, Gundabattini Edison

Acta Mechanica et Automatica

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2024

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Vol. 18, no. 3

474--482

EN

Nano-enhanced refrigerants are substances in which the nanoparticles are suspended in the refrigerantatthe desired concentration. They have the potential to improve the performance of refrigeration and air-conditioning systems that use vapour compression. This study focuses on the thermal conductivity of alumina (Al2O3) and cupric oxide (CuO) nanoparticles immersed in 2,3,3,3-tetrafluoropropene (R1234yf). The thermal conductivity of nano-refrigerants was investigated using appropriate models from earlier studies where the volume concentration of particles and temperatures were varied from 1% to 5% and from 273 K to 323K, respectively. The acquired results are supported by prior experimental investigations on R134a-based nano-refrigerants undertaken by the researchers. The main investigation results indicate that the thermal conductivity of Al2O3/R1234yf and CuO/R1234yf is enhanced with the particle concentrations, interfacial layer thickness, and temperature. Also, the thermal conductivity of Al2O3/R1234yf and CuO/R1234yf decreases with particle size. The thermal conductivity of Al2O3/R1234yf and CuO/R1234yf nano-refrigerants become enhanced with a volume concentration of nano-sized particles by 41.2% and 148.1% respectively at 5% volume concentration and 323K temperature. The thermal conductivity of Al2O3/R1234yf reduces with temperature, by upto 3% of nanoparticle addition and after that, it enhances. Meanwhile, it declines with temperature, by upto 1% of CuO nanoparticle inclusion for CuO/R1234yf. CuO/R1234yf has a thermal conductivity of 16.69% greater than Al2O3/R1234yf at a 5% volume concentration. This paper also concludes that, among the models for thermal conductivity study, Stiprasert’s model is the most accurate and advanced.

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Performance estimation of blended nano-refrigerants’ thermodynamic characteristics and refrigeration efficacy

Mystkowski Arkadiusz, Śmierciew Kamil, Dudar Adam, Gundabattini Edison, Katoch Anirudh, Razak Fadil Abdul, Suresh Arjun, Bibin Baiju S., Farina Adriana R., Cirillo Luca

Acta Mechanica et Automatica

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2024

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Vol. 18, no. 2

282--290

EN

The use of nanoparticle-infused blended refrigerants is essential for achieving an effective sustainable system. This investigation analyses the efficiency of three nano-refrigerants (CuO-R152a, TiO2-R152a and TiO2-R113a) on the basis of the thermal performance and energy usage of the compressor using MATLAB-Simulink in the vapour compression refrigeration cycle with a two-phase flow domain. Also, nanoparticle volume concentrations of 0.1%–0.5% in the basic refrigerants are investigated. In the Simulink model, the outcomes are calculated mathematically. Using the NIST chemistry webbook, the thermo-physical characteristics of base refrigerants were calculated, and different numerical models were used to compute the characteristics of nano-enhanced refrigerants. MS Excel was used to perform the liquid–vapour interpolation. It was discovered that refrigerants with nanoparticles have superior heat-transfer properties and operate most excellently at an optimal volume fraction of 0.1% for TiO2-R152a and CuO-R152a with a coefficient of performance (COP) as 10.8. However, the other blended nano-refrigerant TiO2-R113a performed the best at 0.5% of nano-particle volume fraction with a COP value of 5.27.