Eventos Anais de eventos
ENCIT 2016
16th Brazilian Congress of Thermal Sciences and Engineering
A THEORETICAL ANALYSIS ON THE USE OF PHASE CHANGE MATERIALS IN HOUSEHOLD REFRIGERATORS
Submission Author:
Carla Soares Rametta , SC
Co-Authors:
Joel Boeng, Joaquim Manoel Gonçalves, claudio melo
Presenter: Carla Soares Rametta
doi://10.26678/ABCM.ENCIT2016.CIT2016-0025
Abstract
Conventional household refrigeration systems have reached a point where considerable effort is required to achieve minimal energy savings. Thus, innovative solutions are welcome and the introduction of phase change materials (PCMs) - substances with a high heat fusion which are capable of storing and releasing large amounts of energy - are a good option for performance improvements. This paper introduces a theoretical analysis of the effect of incorporating PCMs into the refrigerated compartments and the condenser of a household refrigerator. From the literature it is clear that the use of PCMs contributes to the system performance, leading to energy savings. Moreover, the incorporation of PCMs into refrigerator compartments brings temperature stabilization, enhances the food preservation capability and keeps the internal temperature at an acceptable level for longer periods in cases of energy shortage. In this paper we describe how a PCM attenuates the difference between condensing and evaporating temperatures and the behavior of this attenuation as a function of the compressor run time ratio and the global heat transfer coefficients between the system components and PCMs. The coefficient of performance (COP) is evaluated and the values in an ideal cycle with and without PCMs are compared. It can be concluded that the addition of PCMs promotes a positive effect in the system, which can be quantified by the design characteristics of its components. The closer the compressor run time ratio is to unity, the smaller the effect of the PCM, this becoming ineffective in the case of variable capacity compressors (VCCs). It was also observed that the wrapping of the heat exchanger is the most efficient way to apply such materials, minimizing the heat transfer resistance.
Keywords
Phase Change Material, Household Refrigerator, theoretical analysis, Phase Change Material, Household Refrigerator, theoretical analysis
