Zakaria Triki¹, Ahmed Selloum¹, Younes Chiba¹, Hichem Tahraoui^1,2, Dorsaf Mansour³, Abdeltif Amrane^4,*, Meriem Zamouche⁵, Mohammed Kebir⁶, Jie Zhang⁷

Frontiers in Heat and Mass Transfer, Vol.22, No.4, pp. 1107-1128, 2024, DOI:10.32604/fhmt.2024.052223 - 30 August 2024

Abstract Refrigeration plays a significant role across various aspects of human life and consumes substantial amounts of electrical energy. The rapid advancement of green cooling technology presents numerous solar-powered refrigeration systems as viable alternatives to traditional refrigeration equipment. Exergy analysis is a key in identifying actual thermodynamic losses and improving the environmental and economic efficiency of refrigeration systems. In this study exergy analyze has been conducted for a solar-powered vapor compression refrigeration (SP-VCR) system in the region of Ghardaïa (Southern Algeria) utilizing R1234ze(E) fluid as an eco-friendly substitute for R134a refrigerant. A MATLAB-based numerical model was… More >

Kolthoum Missaoui^1,2,*, Nader Frikha^2,3, Abdelhamid Kheiri¹, Slimane Gabsi^2,3, Mohammed El Ganaoui⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.4, pp. 1067-1081, 2023, DOI:10.32604/fdmp.2022.021969 - 02 November 2022

Abstract A study is conducted on the performances of a solar powered continuous-adsorption refrigerator considering two particular days as references cases, namely, the summer solstice (June 21st) and the autumn equinox (September 21st). The cooling capacity, system performance coefficient and the daily rate of available cooling energy are assessed. The main goal is to compare the performances of a solar adsorption chiller equipped with a hot water tank (HWT) with an equivalent system relying on solar collectors with no heat storage module. The daily cooling rates for the solar refrigerator are found to be 102.4 kWh More >

Vijay W. Bhatkar^a,*, Anirban Sur^b,*, Anindita Roy^b

Frontiers in Heat and Mass Transfer, Vol.19, pp. 1-7, 2022, DOI:10.5098/hmt.19.15

Abstract Versatile vapor compression refrigeration system is designed, developed and fabricated such that desired condensing and evaporating temperatures can be obtained by providing different electronic controls for superheating, subcooling, fan speed, air heaters and water heatersto use alternative refrigerants to R134a such as R1234ze, R152a, R600a, R290 and R290/R600a (50/50%) with conventional and minichannel condenser. All the refrigerant are tested for condensing temperature ranging from 40 °C to 55 °C while evaporating temperature changes from -10 °C to 15 °C for both condensers. The total exergy loss for main system components such as compressor, condenser, expansion… More >

Felipe Mercês Biglia¹, Raquel da Cunha Ribeiro da Silva², Fátima de Moraes Lino³, Kamal Abdel Radi Ismail³, Thiago Antonini Alves^4,*

Energy Engineering, Vol.119, No.5, pp. 1771-1788, 2022, DOI:10.32604/ee.2022.019625 - 21 July 2022

Abstract The frost growth on cold surfaces in evaporators is an undesirable phenomenon which becomes a problem for the thermal efficiency of the refrigeration systems because the ice layer acts as a thermal insulation, drastically reducing the rate of heat transfer in the system. Its accumulation implies an increase in energy demand and a decrease in the performance of various components involved in the refrigeration process, reducing its efficiency and making it necessary to periodically remove the frost, resulting in expenses for the defrost process. In the present work, a numerical-experimental analysis was performed in order… More >

Jianlu Cheng¹, Kaiyong Hu^1,*, Jiang Shen¹, Lu Jia^1,2, Rui Niu¹, Zhaoxian Yang³

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.4, pp. 1049-1066, 2022, DOI:10.32604/fdmp.2022.019007 - 06 April 2022

Abstract The use of ammonia in large-scale refrigeration systems (such as those used for a stadium) requires adequate ammonia leakage prevention mechanisms are put in place. In the present study, numerical simulations have been conducted to study the dispersion law in the ammonia machinery room of the refrigeration system for the 2022 Beijing Winter Olympics. The wind speed, and release location have been varied to investigate their effects on the dispersion profile. Different positions of the leakage points in the ammonia storage tank have been found to lead to different areas affected accordingly. In general, the More >

Jianghao Niu^*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.6, pp. 1003-1013, 2021, DOI:10.32604/fdmp.2021.015225 - 08 September 2021

Abstract The falling film of an ionic liquid ([EMIM] [DMP] + H₂O) and its effect on a refrigeration system are numerically simulated in the framework of a Volume of Fluid (VOF) method (as available in the ANSYS Fluent computational platform). The properties of the liquid film and the wall shear stress (WSS) are compared with those obtained for a potassium bromide solution. Different working conditions are considered. It is noted that the ionic liquid demonstrates a better absorption capability, with a coefficient of performance (COP) of 0.55. It is proved that the [EMIM] [DMP] + H₂O ionic More >

Piyanut Saengsikhiao¹, Juntakan Taweekun^1,2,*, Kittinan Maliwan², Somchai Sae-ung², Thanansak Theppaya²

Energy Engineering, Vol.118, No.2, pp. 411-433, 2021, DOI:10.32604/EE.2021.012860 - 23 December 2020

Abstract This paper presents the improvement of eco-friendly and power consumption saving refrigerants for refrigeration systems. The novel azeotropic refrigerant mixtures of HFCs and HCs can replace refrigeration systems, and using the R134, R32, R125, and R1270 refrigerants in several compositions found using the decision tree function of the RapidMiner software (which came first in the KDnuggets annual software poll). All refrigerant results are mixed of POE, which is A1 classification refrigerant, non-flammable, and innocuous refrigerant, and using REFPROP software and CYCLE_D-HX software are under the CAN/ANSI/AHRI540 standards. The boiling point of the new refrigerant mix… More >

Jing Hu^a,* , Mingxing Du^b

Frontiers in Heat and Mass Transfer, Vol.14, pp. 1-7, 2020, DOI:10.5098/hmt.14.5

Abstract Inert gases are conveniently used for leak detection. Relative to CO₂, majority of the inert gases are non-condensable. It is of great significance to understand the effects of residual non-condensable gases on the performance of a refrigeration system. This paper investigates, both theoretically and experimentally, on the impact of residual non-condensable gases on the performance of a carbon dioxide (CO₂) evaporator and the system performance. A theoretical analysis indicates that residual non-condensable gases can convert homogeneous nucleation into a heterogeneous nucleation process and accelerate phase change, thus, reducing superheat or incipient boiling temperature. To investigate the… More >

Daoming Shen^1,2,*, Chao Gui¹, Jinhong Xia¹, Songtao Xue^2,3

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.3, pp. 489-500, 2020, DOI:10.32604/fdmp.2020.08969 - 25 May 2020

Abstract The performances of a refrigeration unit relying on compressors working in parallel have been investigated considering the influence of the compressor volumetric efficiency and isentropic efficiency on the compression ratio. Moreover, the following influential factors have been taken into account: evaporation temperature, condensation temperature and compressor suction-exhaust pressure ratio for different opening conditions of the compressor. The following quantities have been selected as the unit performance measurement indicators: refrigeration capacity, energy efficiency ratio (COP), compressor power consumption, and refrigerant flow rate. The experimental results indicate that the system refrigeration capacity and COP decrease with a More >

Hong Hu^a,*, J. N. Chung^a,†

Frontiers in Heat and Mass Transfer, Vol.11, pp. 1-8, 2018, DOI:10.5098/hmt.11.24

Abstract A new architecture for absorption refrigeration systems (ARSs) that enables a significant enhancement of heat and mass transport processes has been proposed. This enhancement in performance is expected to translate into a significant reduction is size and cost of ARSs. The key innovation in the new approach is the use of ultrathin liquid films constrained by highly permeable nanostructured membranes. This approach enables far greater performance than those in the existing macroscale. For example, in the new absorber design, the thin film of LiBr solution is constrained by hydrophobic porous membranes and the inner wall… More >