REFRIGERANT COMPOSITION COMPRISING DIFLUOROMETHANE (HFC32) AND 2,3,3,3-TETRAFLUOROPROPENE (HFO1234YF)

Abstract

An object of the present invention is to provide a refrigerant composition having a reduced amount of comprehensive environmental load, in which the refrigerant composition has low GWP (direct impact on global warming is low), and has good energy efficiency (indirect impact on global warming is low) when used in a device.

The present invention provides a refrigerant composition comprising 30 to 50 mass % of difluoromethane (HFC32) and 70 to 50 mass % of 2,3,3,3-tetrafluoropropene (HFO1234yf).

Claims

1. A refrigerator comprising a refrigerant composition comprising a refrigerant mixture, the refrigerant mixture consisting essentially of 30 to 50 mass % of difluoromethane (HFC32) and 70 to 50 mass % of 2,3,3,3-tetrafluoropropene (HFO1234yf), based on a total of HFC32 and HFO1234yf in the refrigerant composition.

2. The refrigerator according to claim 1, wherein the refrigerator is provided with a countermeasure to prevent heat exchange efficiency from decreasing due to a temperature glide in a heat exchanger.

3. The refrigerator according to claim 2, wherein the refrigerator is further provided with a countermeasure to reduce an effect of pressure loss.

4. The refrigerator according to claim 2, wherein the countermeasure to prevent heat exchange efficiency from decreasing due to the temperature glide in a heat exchanger is at least one of the following: eliminating a temperature difference between air and refrigerant by countercurrent flow, preventing frost formation near an inlet of an evaporator, and increasing a heat-transfer coefficient of a heat exchanger.

5. The refrigerator according to claim 3, wherein the countermeasure to reduce the effect of pressure loss is at least one of the following: increasing a tube diameter of a heat exchanger or optimizing a number of paths in a heat exchanger, increasing a pipe diameter or shortening a length of a pipe in an air conditioner and a connecting pipe for an air conditioner, using an ejector as an expansion mechanism; and using an economizer cycle.

6. A refrigerator comprising a refrigerant composition comprising a refrigerant mixture, the refrigerant mixture consisting essentially of 30 to 45 mass % of difluoromethane (HFC32) and 70 to 55 mass % of 2,3,3,3-tetrafluoropropene (HFO1234yf), based on a total of HFC32 and HFO1234yf in the refrigerant composition.

7. The refrigerator according to claim 6, wherein the refrigerator is provided with a countermeasure to prevent heat exchange efficiency from decreasing due to a temperature glide in a heat exchanger.

8. The refrigerator according to claim 7, wherein the refrigeration unit is further provided with a countermeasure to reduce an effect of pressure loss.

9. A method for operating a refrigerator, comprising causing a refrigerant composition comprising a refrigerant mixture, the refrigerant mixture consisting essentially of 30 to 50 mass % of difluoromethane (HFC32) and 70 to 50 mass % of 2,3,3,3-tetrafluoropropene (HFO1234yf), based on a total of HFC32 and HFO1234yf in the refrigerant composition, to flow in a refrigerator.

10. The method for operating a refrigerator according to claim 9, wherein the refrigerator is provided with a countermeasure to prevent heat exchange efficiency from decreasing due to a temperature glide in a heat exchanger.

11. The method for operating a refrigerator according to claim 10, wherein the refrigerator is further provided with a countermeasure to reduce an effect of pressure loss.

12. The method for operating a refrigerator according to claim 10, wherein the countermeasure to prevent heat exchange efficiency from decreasing due to the temperature glide in a heat exchanger is at least one of the following: eliminating a temperature difference between air and refrigerant by countercurrent flow, preventing frost formation near an inlet of an evaporator, and increasing a heat-transfer coefficient of a heat exchanger.

13. The method for operating a refrigerator according to claim 11, wherein the countermeasure to reduce the effect of pressure loss is at least one of the following: increasing a tube diameter of a heat exchanger or optimizing a number of paths in a heat exchanger, increasing a pipe diameter or shortening a length of a pipe in an air conditioner and a connecting pipe for an air conditioner, using an ejector as an expansion mechanism; and using an economizer cycle.

Description

EXAMPLES

[0048] Hereinbelow, the present invention is described using examples, but is not limited thereto.

[0049] A performance test was conducted in accordance with JIS-C9612 by installing an air conditioner in a calorimeter test chamber approved by JIS. Specifically, the following values were measured: (1) amount of air-side heat exchange in an indoor unit, (2) input power of a compressor, (3) input power of fans in indoor and outdoor units, (4) input current of a four-way switching valve, (5) input current of an electric expansion valve, and (6) input current of a compressor. Then, the coefficient of performance (COP) during each of the following operations was determined: rated cooling operation (4 kW), mid-capacity cooling operation (2 kW), rated heating operation (5 kW), and mid-capacity heating operation (2.5 kW). Further, the APF was determined.

[0050] Table 1 shows the refrigerant compositions used, the specifications of the air conditioners used, and the APF values obtained. Table 1 also shows ratios obtained by comparing each APF with the APF of Comparative Example 1.

TABLE-US-00001 TABLE 1 Refrigerant Air Conditioner Composition Specifications APF Comparative R410A Standard unit 5.99  100% Example 1 for R410A Comparative HFO1234yf Standard unit 4.80 80.1% Example 2 for R410A Comparative HFC32/HFO1234yf Standard unit 4.75 79.3% Example 3 (10/90 mass %) for R410A Example 1 HFC32/HFO1234yf Standard unit 5.36 89.5% (50/50 mass %) for R410A Example 2 HFC32/HFO1234yf Standard unit 5.27 88.0% (40/60 mass %) for R410A Example 3 HFC32/HFO1234yf Specifications 6.10  102% (50/50 mass %) including a countermeasure for temperature glide Example 4 HFC32/HFO1234yf Specifications 6.00  100% (40/60 mass %) including a countermeasure for temperature glide Example 5 HFC32/HFO1234yf Specifications 6.11  102% (40/60 mass %) including countermeasures for temperature glide + pressure loss Specifications including a countermeasure for temperature glide: modified specifications in which a switching valve is provided to a standard unit for R410A so as to allow refrigerant and air to flow entirely in a countercurrent manner in indoor and outdoor heat exchangers during a cooling operation mode and a heating operation mode. Specifications including a countermeasure for pressure loss: specifications in which a dry valve is removed from an indoor heat exchanger of a standard unit for R410A, and the size of a gas-side connecting pipe is changed from 3/8-inch to 4/8-inch.

INDUSTRIAL APPLICABILITY

[0051] The present invention is useful as a refrigerant composition for refrigeration units such as air conditioners, refrigeration machines, and the like.