Enhancements in domestic refrigeration, approaching a sustainable refrigerator – A review

Onarinde

Comp Rev Food Sci Food Safe

2016

108

The domestic refrigerator is now a common household device with very few households in the developed world not possessing 1, or more, for the storage of chilled foods. Domestic storage is the last, and in many respects the most important, link in the food chill chain. Inadequate domestic refrigeration or cooling is frequently cited as a factor in incidents of food poisoning. The authors reviewed the temperature performance of refrigerators in 2008. This new review builds on that review, covering studies that have been published since (and those that were unfortunately missed in the first review), and also seeks to put this important stage of the food cold chain in its context. It is clear from the published data that many refrigerators throughout the world are running at higher than recommended temperatures. It is also clear that, despite improvements in energy use, the temperature performance and use of refrigerators have not changed significantly in the last 40 or so years. Many householders still remain unaware of the recommended refrigeration temperature range, how to ensure that the correct refrigeration temperature range is achieved, the importance of monitoring that it is being maintained, and the potential hazards of temperature abuse.

Section: Energy Consumption and Wastementioning

confidence: 99%

The Use and Performance of Household Refrigerators: A Review

Onarinde

Comp Rev Food Sci Food Safe

2016

108

Renewable and Sustainable Energy Reviews

“…As a final safety remark, Belman et al [43] highlighted the refrigerant charge as a key parameter in vapour compression system applications in the domestic sector. A lower refrigerant charge can reduce the final cost of the system and provide safer and more efficient vapour compression systems.…”

Section: Materials Compatibilitymentioning

confidence: 99%

Refrigerant R32 as lower GWP working fluid in residential air conditioning systems in Europe and the USA

Mota-Babiloni

Navarro-Esbrí

Makhnatch

et al. 2017

103

Because air conditioning and heat pump systems contribute greatly to greenhouse gas emissions, equipment with both lower global warming potential (GWP) working fluids and a higher level of performance should be used. R32 (difluoromethane) has been proposed to substitute R410A, particularly in residential air conditioning (RAC) systems. This study collected the most relevant and recent researches into R32 as a refrigerant so as to assess its viability in RAC systems in both Europe and the USA, as compared to R410A and other lower GWP RAC alternatives.The R32 value of GWP is 677, which is below the F-gas regulation limit in RAC equipment (750). According to ASHRAE standard 34, R32 is less flammable than hydrocarbons, and the amount of charge permitted for R32 is above the necessary level in RAC equipment. It can be concluded that R32 has significantly good heat transfer characteristics and a level of performance that make it acceptable at low condensing temperatures, thereby avoiding overly high compressor discharge temperatures. Its performance is very similar to that of R410A across the entire operating range, and it is therefore believed that R32 will be utilized in RAC systems in the remaining countries that prioritize lower GWP fluids but are less strict in their security regulations.To replace R410A under extreme conditions, some system modifications can be conducted, or R32 mixtures with hydrofluoroolefins (HFOs) can be used. Such mixtures achieve a lower performance than R32, but are acceptable replacements when considering their lower GWP compared to that of R32, and similar level of flammability. Finally, other (R32-based) alternative mixtures have also been developed and their behaviours studied under a wide range of operating conditions.

“…For instance, the fresh food compartment is the biggest in a domestic refrigerator. In this compartment, food must be kept at 3 • C in most refrigerators when the damper position is 5 (see [1]). This compartment is usually divided by the shelves in order to make the food organization easy for the user.…”

Section: Techniques For Designing the Fresh Food Compartmentmentioning

confidence: 99%

“…The domestic refrigerator is one of the most used appliances worldwide and the majority of these refrigerators are based on the vapor compression technology; thus, in literature, several studies have focused on thermal improvements and energy strategies in the system operation [1,2]. On the other hand, it is known that the basic function of the refrigerator is storing fresh food and medicines, and this depends on the good performance of the refrigerator, which is closely linked to temperature distribution and air flow inside the compartments.…”

Section: Introductionmentioning

confidence: 99%

Thermal Simulation of the Fresh Food Compartment in a Domestic Refrigerator

et al. 2017

Abstract:In the field of domestic refrigeration, it is important to look for methods that can be used to simulate, and, thus, improve the thermal behavior of the fresh food compartment. In this sense, this study proposes some methods to model the thermal behavior of this compartment when the shelves' positions are changed. Temperature measurements at specific locations in this compartment were obtained. Several shelf position combinations were performed to use three 2D interpolation methods in order to simulate the temperature mean and the temperature variance. The methods used were: Lagrange's interpolation, cubic spline interpolation and bilinear interpolation. Two validation points were chosen to verify the proposed methods. By comparing the experimental results with the computer simulations, it was possible to conclude that the method of Lagrange's interpolation provided values that were not close to the real measured values. On the other hand, it was observed that the method of bilinear interpolation offered the best results, estimating values which were very close to the actual experimental measurements. These interpolation methods were used to build color thermal graphs that can be used to find some of the most appropriate shelf position combinations in this type of refrigerator. By inspection of these thermal graphs, it can be seen that the lowest average temperature was obtained when one shelf was located at 24.5 cm while the second shelf was located at 29.5 cm measured from the top of the compartment. In the same way, it can be seen that the minimum temperature variance was obtained when only one shelf was inside the compartment and this shelf was located at 29.5 cm.