Challenges in implementation of a moving coil linear compressor in a household refrigerator
TL;DR: A linear compressor is well known for its excellent performance in Stirling cryocooler, space application and minimum linkages, lesser friction points and lower noise characteristics make the linear compressor a good choice for space application.
Abstract: A linear compressor is well known for its excellent performance in Stirling cryocooler, space application. Minimum linkages, lesser friction points and lower noise characteristics make the linear c...
Citations
More filters
Abstract: The efficiency improvement of household refrigerators is of significance to electricity consumption reduction of residential buildings The cold loss recovery in household refrigerators is a promising development direction In this study, a refrigerator improved by heat pipes is designed to reduce the cold loss at freezer walls to enhance the overall efficiency of the refrigerator A complete steady-state mathematical model is built for characterizing its overall energy saving behaviors by introducing the real structural parameters of a Midea BCD-111 refrigerator and measured temperature boundary conditions The performances of the improved refrigerator are investigated with typical operating states, variable ambient temperature, and heat pipe design The simulative results indicate that the cold loss of the freezer of the improved refrigerator can be reduced by 83–165%, and the energy saving capability is relatively reliable Results verify that the cold loss recovery of the improved refrigerator is feasible in various operating conditions
5 citations
References
More filters
TL;DR: A review of linear compressors for domestic refrigeration and electronics cooling is presented in this article, where the challenges associated with the linear compressor are also discussed to provide a comprehensive review of the technology for research and development in future.
Abstract: Linear compressor has no crank mechanism compared with conventional reciprocating compressor. This allows higher efficiency, oil-free operation, lower cost and smaller size when linear compressors are used for vapour compression refrigeration (VCR) system. Typically, a linear compressor consists of a linear motor (connected to a piston) and suspension springs, operated at resonant frequency. This paper presents a review of linear compressors for refrigeration system. Different designs and modelling of linear compressors for both domestic refrigeration and electronics cooling (miniature VCR system) are discussed. Key characteristics of linear compressor are also described, including motor type, compressor loss, piston sensing and control, piston drift and resonance. The challenges associated with the linear compressors are also discussed to provide a comprehensive review of the technology for research and development in future.
88 citations
TL;DR: In this article, an oil-free moving magnet linear compressor with clearance seals and flexure springs was designed for incorporation into a vapour compression refrigeration system with compact heat exchangers for applications such as electronics cooling.
Abstract: A new type of oil-free moving magnet linear compressor with clearance seals and flexure springs has been designed for incorporation into a vapour compression refrigeration system with compact heat exchangers for applications such as electronics cooling. A linear compressor prototype was built with a maximum stroke of 14 mm and a piston diameter of 19 mm. An experimental apparatus was built to measure the compressor efficiencies and coefficient of performance (COP) of a refrigeration system with the linear compressor, using R134a. The resonant frequency for each operating condition was predicted using the discharge pressure, suction pressure and stroke. Refrigeration measurements were conducted for different strokes under each pressure ratio with a fixed condenser outlet temperature of 50 �C and evaporator temperature ranging from 6 �C to 27 �C. The results show that the COPs are around 3.0 for tests with a pressure ratio of 2.5 (evaporator temperature of 20 �C).
54 citations
TL;DR: In this article, the impact of dead (clearance) volume on both a linear and reciprocating compressor is analyzed and it is shown that the linear compressor remains relatively unaffected by an increase in dead volume up to a certain point.
Abstract: A comprehensive model of a linear compressor for electronics cooling was previously presented by Bradshaw et al. (2011) then enhanced and used for a sensitivity analysis of the leakage gap, eccentricity, and piston geometry by Bradshaw et al. (2013). The current work utilizes the previously developed model to explore the energy recovery characteristics of a linear compressor as compared to those of a reciprocating compressor. The impact of dead (clearance) volume on both a linear and reciprocating compressor is analyzed. In contrast to a reciprocating compressor the overall isentropic efficiency of the linear compressor remains relatively unaffected by an increase in dead volume up to a certain point. This behavior is attributed to the ability of the linear compressor to recapture the energy of the compressed gas during the expansion process. This characteristic behavior allows a linear compressor to be used for efficient capacity control from roughly 35–100%.
43 citations
TL;DR: In this article, an inherent capacity modulated (ICM) linear compressor was proposed and evaluated with the cooling capacity ratio varying from 50 to 100% at an evaporating temperature of −26 −C and a condensing temperature of 38 −C. The ICM linear compressor is capable of modulating its capacity independently without requiring stroke controllers.
Abstract: A linear compressor requires stroke controllers, as the piston movement is sensitive to the ambient temperature. This paper presents the performance characteristics of an inherent capacity-modulated (ICM) linear compressor. The compressor is capable of modulating its capacity independently without requiring stroke controllers. Electric parameters are designed to deliver inherent capacity modulation in accordance with variations in the cooling demand. An inherent capacity modulation method according to cooling demand levels was proposed and a prototype compressor was constructed. Its performance was evaluated with the cooling capacity ratio varying from 50 to 100% at an evaporating temperature of −26 °C and a condensing temperature of 38 °C. The total efficiency of the ICM linear compressor was as high as that of an electrical resonant system. This shows that the COP difference between the ICM linear compressor and the linear compressor controlled by an electrical resonance system appeared to be less than 1% over a wide cooling capacity ratio range of 50–100%. The results for the conventional linear compressor did not account for the power consumed by the electronic drive, so thus the ICM linear compressor had the potential improvement for energy saving.
38 citations
TL;DR: In this paper, a prototype of the linear compressor with moving coil type linear motor has been developed and the developed compressor is integrated with test loop using R134a refrigerant to confirm its performance.
Abstract: A prototype of the compressor with moving coil type linear motor has been developed. The developed compressor is integrated with test loop using R134a refrigerant to confirm its performance. The simulation results are validated with the experimental data. The experimental results from the test loop with strokes of 10, 11 and 12 mm for three different pressure ratios of 4, 7, 10 are presented and discussed in this paper. The COP of the system calculated is 1.4 from the test results (for 54 °C condenser temperature and −20 °C evaporator temperature) with the stroke of 10 mm, pressure ratio of 10 and cooling capacity of 134 W. The maximum COP of 2.13 is achieved (for 54 °C condenser temperature and 2 °C evaporator temperature) with the stroke of 12 mm, pressure ratio of 4 and cooling capacity of 325 W. Normal refrigerator compressors utilize lubricant oil but as the refrigerant is changed the oil suitable for particular refrigerant also needs to be changed. The novel linear compressor tested does not utilize lubricant oil. The linear compressor has only one friction point i.e. between the piston and cylinder. The linear compressor utilizes Rulon (low coefficient of friction material) as a special material coated on the piston surface in contact with the cylinder. The oil-free operation of the compressor helps in adapting the refrigerator to different refrigerants without having to consider a change of lubricating oil. Refrigeration system performance with both linear compressor and the conventional reciprocating compressor is measured and compared. System COP with the linear compressor is 18.6% more than with the commercially available reciprocating compressor. The absence of connecting rod and crank mechanism accompanied with oil-free operation due to reduced friction enhance the performance of the linear compressor.
26 citations