Refrigeration cycle apparatus

Abstract

A refrigeration cycle apparatus (1) is capable of performing a refrigeration cycle using a small-GWP refrigerant. The refrigeration cycle apparatus (1) includes a refrigerant circuit (10) and a refrigerant enclosed in the refrigerant circuit (10). The refrigerant circuit includes a compressor (21), a condenser (23), a decompressing section (24), and an evaporator (31). The refrigerant contains at least 1,2-difluoroethylene.

1 . A refrigeration cycle apparatus comprising:
 a refrigerant circuit including a compressor, a condenser, a decompressing section, and an evaporator; and   a refrigerant containing at least 1,2-difluoroethylene enclosed in the refrigerant circuit.   
     
     
         2 . The refrigeration cycle apparatus according to  claim 1 ,
 wherein the refrigerant comprises trans-1,2-difluoroethylene (HFO-1132 (E)), trifluoroethylene (HFO-1123), and 2,3,3,3-tetrafluoro-1-propene (R1234yf).   
     
     
         3 . The refrigeration cycle apparatus according to  claim 2 ,
 wherein
 when the mass % of HFO-1132(E), HFO-1123, and R1234yf based on their sum in the refrigerant is respectively represented by x, y, and z, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), HFO-1123, and R1234yf is 100 mass % are within the range of a figure surrounded by line segments OD, DG, GH, and HO that connect the following 4 points: 
   point D (87.6, 0.0, 12.4),   point G (18.2, 55.1, 26.7),   point H (56.7, 43.3, 0.0), and   point O (100.0, 0.0, 0.0),   or on the line segments OD, DG, and GH (excluding the points O and H);
 the line segment DG is represented by coordinates 
   (0.0047y 2 −1.5177y+87.598, y, −0.0047y 2 +0.5177y+12.402),
 the line segment GH is represented by coordinates 
   (−0.0134z 2 −1.0825z+56.692, 0.0134z 2 +0.0825z+43.308, z), and
 the line segments HO and OD are straight lines. 
   
     
     
         4 . The refrigeration cycle apparatus according to  claim 2 ,
 wherein
 when the mass % of HFO-1132(E), HFO-1123, and R1234yf based on their sum in the refrigerant is respectively represented by x, y, and z, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), HFO-1123, and R1234yf is 100 mass % are within the range of a figure surrounded by line segments LG, GH, HI, and IL that connect the following 4 points: 
   point L (72.5, 10.2, 17.3),   point G (18.2, 55.1, 26.7),   point H (56.7, 43.3, 0.0), and   point I (72.5, 27.5, 0.0),   or on the line segments LG, GH, and IL (excluding the points H and I);
 the line segment LG is represented by coordinates (0.0047y 2 −1.5177y+87.598, y, −0.0047y 2 +0.5177y+12.402), 
 the line segment GH is represented by coordinates (−0.0134z 2 −1.0825z+56.692, 0.0134z 2 +0.0825z+43.308, z), and 
 the line segments HI and IL are straight lines. 
   
     
     
         5 . The refrigeration cycle apparatus according to  claim 2 , further comprising difluoromethane (R32). 
     
     
         6 . The refrigeration cycle apparatus according to  claim 5 ,
 wherein
 when the mass % of HFO-1132(E), HFO-1123, R1234yf, and R32 based on their sum in the refrigerant is respectively represented by x, y, z, and a, 
 if 0<a≤10.0, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), HFO-1123, and R1234yf is 100 mass % are within the range of a figure surrounded by straight lines that connect the following 4 points: 
   point A (0.02a 2 −2.46a+93.4, 0, −0.02a 2 +2.46a+6.6),   point B′ (−0.008a 2 −1.38a+56, 0.018a 2 −0.53a+26.3, −0.01a 2 +1.91a+17.7),   point C (−0.016a 2 +1.02a+77.6, 0.016a 2 −1.02a+22.4, 0), and   point O (100.0, 0.0, 0.0),   or on the straight lines OA, AB′, and B′C (excluding point O and point C);
 if 10.0<a≤16.5, coordinates (x,y,z) in the ternary composition diagram are within the range of a figure surrounded by straight lines that connect the following 4 points: 
   point A (0.0244a 2 −2.5695a+94.056, 0, −0.0244a 2 +2.5695a+5.944),   point B′ (0.1161a 2 −1.9959a+59.749, 0.014a 2 −0.3399a+24.8, −0.1301a 2 +2.3358a+15.451),   point C (−0.0161a 2 +1.02a+77.6, 0.0161a 2 −1.02a+22.4, 0), and   point O (100.0, 0.0, 0.0),   or on the straight lines OA, AB′, and B′C (excluding point O and point C); or
 if 16.5<a≤21.8, coordinates (x,y,z) in the ternary composition diagram are within the range of a figure surrounded by straight lines that connect the following 4 points: 
   point A (0.0161a 2 −2.3535a+92.742, 0, −0.0161a 2 +2.3535a+7.258),   point B′ (−0.0435a 2 −0.0435a+50.406, −0.0304a 2 +1.8991a−0.0661, 0.0739a 2 −1.8556a+49.6601),   point C (−0.0161a 2 +0.9959a+77.851, 0.0161a 2 −0.9959a+22.149, 0), and   point O (100.0, 0.0, 0.0),   or on the straight lines OA, AB′, and B′C (excluding point O and point C).   
     
     
         7 . The refrigeration cycle apparatus according to  claim 1 ,
 the refrigerant comprising trans-1,2-difluoroethylene (HFO-1132 (E)), trifluoroethylene (HFO-1123) in a total amount of 99.5 mass % or more based on the entire refrigerant, and   the refrigerant comprising 62.5 mass % to 72.5 mass % of HFO-1132(E) based on the entire refrigerant.   
     
     
         8 . The refrigeration cycle apparatus according to  claim 1 ,
 the refrigerant comprising trans-1,2-difluoroethylene (HFO-1132(E)), difluoromethane (R32), and 2,3,3,3-tetrafluoro-1-propene (R1234yf),   
       wherein
 when the mass % of HFO-1132(E), R32, and R1234yf based on their sum in the refrigerant is respectively represented by x, y, and z, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), R32, and R1234yf is 100 mass % are within the range of a figure surrounded by line segments AC, CF, FD, and DA that connect the following 4 points: 
 
       point A (71.1, 0.0, 28.9), 
       point C (36.5, 18.2, 45.3), 
       point F (47.6, 18.3, 34.1), and 
       point D (72.0, 0.0, 28.0), 
       or on these line segments;
 the line segment AC is represented by coordinates (0.0181y 2 −2.2288y+71.096, y, −0.0181y 2 +1.2288y+28.904), 
 the line segment FD is represented by coordinates (0.02y 2 −1.7y+72, y, −0.02y 2 +0.7y+28), and 
 the line segments CF and DA are straight lines. 
 
     
     
         9 . The refrigeration cycle apparatus according to  claim 1 ,
 the refrigerant comprising trans-1,2-difluoroethylene (HFO-1132(E)), difluoromethane (R32), and 2,3,3,3-tetrafluoro-1-propene (R1234yf),   
       wherein
 when the mass % of HFO-1132(E), R32, and R1234yf based on their sum in the refrigerant is respectively represented by x, y, and z, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), R32, and R1234yf is 100 mass % are within the range of a figure surrounded by line segments AB, BE, ED, and DA that connect the following 4 points: 
 
       point A (71.1, 0.0, 28.9), 
       point B (42.6, 14.5, 42.9), 
       point E (51.4, 14.6, 34.0), and 
       point D (72.0, 0.0, 28.0), 
       or on these line segments;
 the line segment AB is represented by coordinates (0.0181y 2 −2.2288y+71.096, y, −0.0181y 2 +1.2288y+28.904), 
 the line segment ED is represented by coordinates (0.02y 2 −1.7y+72, y, −0.02y 2 +0.7y+28), and 
 the line segments BE and DA are straight lines. 
 
     
     
         10 . The refrigeration cycle apparatus according to  claim 1 ,
 the refrigerant comprising trans-1,2-difluoroethylene (HFO-1132(E)), difluoromethane (R32), and 2,3,3,3-tetrafluoro-1-propene (R1234yf),   
       wherein
 when the mass % of HFO-1132(E), R32, and R1234yf based on their sum in the refrigerant is respectively represented by x, y, and z, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), R32, and R1234yf is 100 mass % are within the range of a figure surrounded by line segments GI, IJ, and JG that connect the following 3 points: 
 
       point G (77.5, 6.9, 15.6), 
       point I (55.1, 18.3, 26.6), and 
       point J (77.5, 18.4, 4.1), 
       or on these line segments;
 the line segment GI is represented by coordinates (0.02y 2 −2.4583y+93.396, y, −0.02y 2 +1.4583y+6.604), and 
 the line segments IJ and JG are straight lines. 
 
     
     
         11 . The refrigeration cycle apparatus according to  claim 1 ,
 the refrigerant comprising trans-1,2-difluoroethylene (HFO-1132(E)), difluoromethane (R32), and 2,3,3,3-tetrafluoro-1-propene (R1234yf),   
       wherein
 when the mass % of HFO-1132(E), R32, and R1234yf based on their sum in the refrigerant is respectively represented by x, y, and z, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), R32, and R1234yf is 100 mass % are within the range of a figure surrounded by line segments GH, HK, and KG that connect the following 3 points: 
 
       point G (77.5, 6.9, 15.6), 
       point H (61.8, 14.6, 23.6), and 
       point K (77.5, 14.6, 7.9), 
       or on these line segments;
 the line segment GH is represented by coordinates (0.02y 2 −2.4583y+93.396, y, −0.02y 2 +1.4583y+6.604), and 
 the line segments HK and KG are straight lines. 
 
     
     
         12 . The refrigeration cycle apparatus according to  claim 1 ,
 the refrigerant comprising trans-1,2-difluoroethylene (HFO-1132(E)), trifluoroethylene (HFO-1123), and difluoromethane (R32),   
       wherein
 when the mass % of HFO-1132(E), HFO-1123, and R32 based on their sum in the refrigerant is respectively represented by x, y, and z, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), HFO-1123, and R32 is 100 mass % are within the range of a figure surrounded by line segments OC′, C′D′, D′E′, E′A′, and A′O that connect the following 5 points: 
 
       point O (100.0, 0.0, 0.0), 
       point C′ (56.7, 43.3, 0.0), 
       point D′ (52.2, 38.3, 9.5), 
       point E′ (41.8, 39.8, 18.4), and 
       point A′ (81.6, 0.0, 18.4), 
       or on the line segments C′D′, D′E′, and E′A′ (excluding the points C′ and A′);
 the line segment C′D′ is represented by coordinates 
 
       (−0.0297z 2 −0.1915z+56.7, 0.0297z 2 +1.1915z+43.3, z),
 the line segment D′E′ is represented by coordinates 
 
       (−0.0535z 2 +0.3229z+53.957, 0.0535z 2 +0.6771z+46.043, z), and
 the line segments OC′, E′A′, and A′O are straight lines. 
 
     
     
         13 . The refrigeration cycle apparatus according to  claim 1 ,
 the refrigerant comprising trans-1,2-difluoroethylene (HFO-1132(E)), trifluoroethylene (HFO-1123), and difluoromethane (R32),   
       wherein
 when the mass % of HFO-1132(E), HFO-1123, and R32 based on their sum in the refrigerant is respectively represented by x, y, and z, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), HFO-1123, and R32 is 100 mass % are within the range of a figure surrounded by line segments OC, CD, DE, EA′, and A′O that connect the following 5 points: 
 
       point O (100.0, 0.0, 0.0), 
       point C (77.7, 22.3, 0.0), 
       point D (76.3, 14.2, 9.5), 
       point E (72.2, 9.4, 18.4), and 
       point A′ (81.6, 0.0, 18.4), 
       or on the line segments CD, DE, and EA′ (excluding the points C and A′);
 the line segment CDE is represented by coordinates 
 
       (−0.017z 2 +0.0148z+77.684, 0.017z 2 +0.9852z+22.316, z), and
 the line segments OC, EA′, and A′O are straight lines. 
 
     
     
         14 . The refrigeration cycle apparatus according to  claim 1 ,
 the refrigerant comprising trans-1,2-difluoroethylene (HFO-1132(E)), trifluoroethylene (HFO-1123), and difluoromethane (R32),   
       wherein
 when the mass % of HFO-1132(E), HFO-1123, and R32 based on their sum in the refrigerant is respectively represented by x, y, and z, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), HFO-1123, and R32 is 100 mass % are within the range of a figure surrounded by line segments OC′, C′D′, D′A, and AO that connect the following points: 
 
       point O (100.0, 0.0, 0.0), 
       point C′ (56.7, 43.3, 0.0), 
       point D′ (52.2, 38.3, 9.5), and 
       point A (90.5, 0.0, 9.5), 
       or on the line segments C′D′ and D′A (excluding the points C′ and A);
 the line segment C′D′ is represented by coordinates 
 
       (−0.0297z 2 −0.1915z+56.7, 0.0297z 2 +1.1915z+43.3, z), and
 the line segments OC′, D′A, and AO are straight lines. 
 
     
     
         15 . The refrigeration cycle apparatus according to  claim 1 ,
 the refrigerant comprising trans-1,2-difluoroethylene (HFO-1132(E)), trifluoroethylene (HFO-1123), and difluoromethane (R32),   
       wherein
 when the mass % of HFO-1132(E), HFO-1123, and R32 based on their sum in the refrigerant is respectively represented by x, y, and z, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), HFO-1123, and R32 is 100 mass % are within the range of a figure surrounded by line segments OC, CD, DA, and AO that connect the following points: 
 
       point O (100.0, 0.0, 0.0), 
       point C (77.7, 22.3, 0.0), 
       point D (76.3, 14.2, 9.5), and 
       point A (90.5, 0.0, 9.5), 
       or on the line segments CD and DA (excluding the points C and A);
 the line segment CD is represented by coordinates 
 
       (−0.017z 2 +0.0148z+77.684, 0.017z 2 +0.9852z+22.316, z), and
 the line segments OC, DA, and AO are straight lines.