Refrigeration apparatus

Abstract

A two-stage refrigeration apparatus ( 500 ) includes a first cycle ( 510 ) and a second cycle ( 520 ). The first cycle ( 510 ) includes a first compressor ( 511 ), a first condenser ( 512 ), a first expansion mechanism ( 513 ), and a first evaporator ( 514 ) that are arranged in such a manner as to be connected to the first cycle. A first refrigerant circulates through the first cycle. The second cycle ( 520 ) includes a second downstream-side condenser ( 523 ) and a second evaporator ( 527 ) that are arranged in such a manner as to be connected to the second cycle. A second refrigerant circulates through the second cycle. The first evaporator ( 514 ) and the second downstream-side condenser ( 523 ) constitute a cascade condenser ( 531 ). In the cascade condenser ( 531 ), heat is exchanged between the first refrigerant and the second refrigerant. At least one of the first refrigerant and the second refrigerant is a refrigerant mixture containing at least 1,2-difluoroethylene (HFO-1132(E)).

1 . A refrigeration apparatus comprising:
 a first cycle including a first compressor, a first radiator, a first expansion mechanism, and a first heat absorber that are arranged in such a manner as to be connected to the first cycle, a first refrigerant circulating through the first cycle; and   a second cycle including a second radiator and a second heat absorber that are arranged in such a manner as to be connected to the second cycle, a second refrigerant circulating through the second cycle, wherein   the first heat absorber and the second radiator constitute a heat exchanger in which heat is exchanged between the first refrigerant flowing through the first heat absorber (RP,  514 ) and the second refrigerant flowing through the second radiator, and   at least one of the first refrigerant and the second refrigerant is a refrigerant mixture containing at least 1,2-difluoroethylene (HFO-1132(E)).   
     
     
         2 . A refrigeration apparatus comprising:
 a first cycle including a first compressor, a first radiator, a first expansion mechanism, and a first heat absorber that are arranged in such a manner as to be connected to the first cycle, a first refrigerant circulating through the first cycle; and   a second cycle including a second radiator and a second heat absorber that are arranged in such a manner as to be connected to the second cycle, a second refrigerant circulating through the second cycle, wherein   the first radiator and the second heat absorber constitute a heat exchanger in which heat is exchanged between the first refrigerant flowing through the first radiator and the second refrigerant flowing through the second heat absorber, and   at least one of the first refrigerant and the second refrigerant is a refrigerant mixture containing at least 1,2-difluoroethylene (HFO-1132(E)).   
     
     
         3 . The refrigeration apparatus according to  claim 1 , wherein
 the second cycle further includes a second compressor and a second expansion mechanism that are arranged in such a manner as to be connected to the second cycle,   the first refrigerant flowing through the first radiator of the first cycle releases heat into outside air,   the first refrigerant is the refrigerant mixture, and   the second refrigerant is carbon dioxide.   
     
     
         4 . The refrigeration apparatus according to  claim 1 , wherein
 the second cycle further includes a second compressor and a second expansion mechanism that are arranged in such a manner as to be connected to the second cycle,   the first refrigerant flowing through the first radiator of the first cycle releases heat into outside air,   the first refrigerant is the refrigerant mixture, and   the second refrigerant is the refrigerant mixture.   
     
     
         5 . The refrigeration apparatus according to  claim 1 , wherein
 the second cycle further includes a second compressor and a second expansion mechanism that are arranged in such a manner as to be connected to the second cycle,   the first refrigerant flowing through the first radiator of the first cycle releases heat into outside air,   the first refrigerant is R32, and   the second refrigerant is the refrigerant mixture.   
     
     
         6 . The refrigeration apparatus according to  claim 1 , wherein
 the first refrigerant flowing through the first radiator of the first cycle (RC) releases heat into outside air,   the first refrigerant is the refrigerant mixture, and   the second refrigerant is a liquid medium.   
     
     
         7 . The refrigeration apparatus according to  claim 2 , wherein
 the second cycle further includes a second compressor and a second expansion mechanism that are arranged in such a manner as to be connected to the second cycle,   the first refrigerant flowing through the first heat absorber of the first cycle takes away heat from outside air,   the first refrigerant is the refrigerant mixture, and   the second refrigerant is a refrigerant whose saturation pressure at a predetermined temperature is lower than a saturation pressure of the refrigerant mixture at the predetermined temperature.   
     
     
         8 . The refrigeration apparatus according to  claim 1 ,
 wherein   the refrigerant mixture comprises trans-1,2-difluoroethylene (HFO-1132(E)), trifluoroethylene (HFO-1123), and 2,3,3,3-tetrafluoro-1-propene (R1234yf).   
     
     
         9 . The refrigeration apparatus according to  claim 8 ,
 wherein   when the mass % of HFO-1132(E), HFO-1123, and R1234yf based on their sum in the refrigerant mixture 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 AA′, A′B, BD, DC′, C′C, CO, and OA that connect the following 7 points:   
       point A (68.6, 0.0, 31.4), 
       point A′ (30.6, 30.0, 39.4), 
       point B (0.0, 58.7, 41.3), 
       point D (0.0, 80.4, 19.6), 
       point C′ (19.5, 70.5, 10.0), 
       point C (32.9, 67.1, 0.0), and 
       point O (100.0, 0.0, 0.0), 
       or on the above line segments (excluding the points on the line segments BD, CO, and OA);
 the line segment AA′ is represented by coordinates (x, 0.0016x 2 −0.9473x+57.497, −0.0016x 2 −0.0527x+42.503), 
 the line segment A′B is represented by coordinates (x, 0.0029x 2 −1.0268x+58.7, −0.0029x 2 +0.0268x+41.3), 
 the line segment DC′ is represented by coordinates (x, 0.0082x 2 −0.6671x+80.4, −0.0082x 2 −0.3329x+19.6), 
 the line segment C′C is represented by coordinates (x, 0.0067x 2 −0.6034x+79.729, −0.0067x 2 −0.3966x+20.271), and 
 the line segments BD, CO, and OA are straight lines. 
 
     
     
         10 . The refrigeration apparatus according to  claim 8 ,
 wherein   when the mass % of HFO-1132(E), HFO-1123, and R1234yf based on their sum in the refrigerant mixture 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 GI, IA, AA′, A′B, BD, DC′, C′C, and CG that connect the following 8 points:   
       point G (72.0, 28.0, 0.0), 
       point I (72.0, 0.0, 28.0), 
       point A (68.6, 0.0, 31.4), 
       point A′ (30.6, 30.0, 39.4), 
       point B (0.0, 58.7, 41.3), 
       point D (0.0, 80.4, 19.6), 
       point C′ (19.5, 70.5, 10.0), and 
       point C (32.9, 67.1, 0.0), 
       or on the above line segments (excluding the points on the line segments IA, BD, and CG);
 the line segment AA′ is represented by coordinates (x, 0.0016x 2 −0.9473x+57.497, −0.0016x 2 −0.0527x+42.503), 
 the line segment A′B is represented by coordinates (x, 0.0029x 2 −1.0268x+58.7, −0.0029x 2 +0.0268x+41.3), 
 the line segment DC′ is represented by coordinates (x, 0.0082x 2 −0.6671x+80.4, −0.0082x 2 −0.3329x+19.6), 
 the line segment C′C is represented by coordinates (x, 0.0067x 2 −0.6034x+79.729, −0.0067x 2 −0.3966x+20.271), and 
 the line segments GI, IA, BD, and CG are straight lines. 
 
     
     
         11 . The refrigeration apparatus according to  claim 8 ,
 wherein   when the mass % of HFO-1132(E), HFO-1123, and R1234yf based on their sum in the refrigerant mixture 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 JP, PN, NK, KA′, A′B, BD, DC′, C′C, and CJ that connect the following 9 points:   
       point J (47.1, 52.9, 0.0), 
       point P (55.8, 42.0, 2.2), 
       point N (68.6, 16.3, 15.1), 
       point K (61.3, 5.4, 33.3), 
       point A′ (30.6, 30.0, 39.4), 
       point B (0.0, 58.7, 41.3), 
       point D (0.0, 80.4, 19.6), 
       point C′ (19.5, 70.5, 10.0), and 
       point C (32.9, 67.1, 0.0), 
       or on the above line segments (excluding the points on the line segments BD and CJ);
 the line segment PN is represented by coordinates (x, −0.1135x 2 +12.112x−280.43, 0.1135x 2 −13.112x+380.43), 
 the line segment NK is represented by coordinates (x, 0.2421x 2 −29.955x+931.91, −0.2421x 2 +28.955x−831.91), 
 the line segment KA′ is represented by coordinates (x, 0.0016x 2 −0.9473x+57.497, −0.0016x 2 −0.0527x+42.503), 
 the line segment A′B is represented by coordinates (x, 0.0029x 2 −1.0268x+58.7, −0.0029x 2 +0.0268x+41.3), 
 the line segment DC′ is represented by coordinates (x, 0.0082x 2 −0.6671x+80.4, −0.0082x 2 −0.3329x+19.6), 
 the line segment C′C is represented by coordinates (x, 0.0067x 2 −0.6034x+79.729, −0.0067x 2 −0.3966x+20.271), and 
 the line segments JP, BD, and CG are straight lines. 
 
     
     
         12 . The refrigeration apparatus according to  claim 8 ,
 wherein   when the mass % of HFO-1132(E), HFO-1123, and R1234yf based on their sum in the refrigerant mixture 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 JP, PL, LM, MA′, A′B, BD, DC′, C′C, and CJ that connect the following 9 points:   
       point J (47.1, 52.9, 0.0), 
       point P (55.8, 42.0, 2.2), 
       point L (63.1, 31.9, 5.0), 
       point M (60.3, 6.2, 33.5), 
       point A′ (30.6, 30.0, 39.4), 
       point B (0.0, 58.7, 41.3), 
       point D (0.0, 80.4, 19.6), 
       point C′ (19.5, 70.5, 10.0), and 
       point C (32.9, 67.1, 0.0), 
       or on the above line segments (excluding the points on the line segments BD and CJ);
 the line segment PL is represented by coordinates (x, −0.1135x 2 +12.112x−280.43, 0.1135x 2 −13.112x+380.43) 
 the line segment MA′ is represented by coordinates (x, 0.0016x 2 −0.9473x+57.497, −0.0016x 2 −0.0527x+42.503), 
 the line segment A′B is represented by coordinates (x, 0.0029x 2 −1.0268x+58.7, −0.0029x 2 +0.0268x+41.3), 
 the line segment DC′ is represented by coordinates (x, 0.0082x 2 −0.6671x+80.4, −0.0082x 2 −0.3329x+19.6), 
 the line segment C′C is represented by coordinates (x, 0.0067x 2 −0.6034x+79.729, −0.0067x 2 −0.3966x+20.271), and 
 the line segments JP, LM, BD, and CG are straight lines. 
 
     
     
         13 . The refrigeration apparatus according to  claim 8 ,
 wherein   when the mass % of HFO-1132(E), HFO-1123, and R1234yf based on their sum in the refrigerant mixture 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 PL, LM, MA′, A′B, BF, FT, and TP that connect the following 7 points:   
       point P (55.8, 42.0, 2.2), 
       point L (63.1, 31.9, 5.0), 
       point M (60.3, 6.2, 33.5), 
       point A′ (30.6, 30.0, 39.4), 
       point B (0.0, 58.7, 41.3), 
       point F (0.0, 61.8, 38.2), and 
       point T (35.8, 44.9, 19.3), 
       or on the above line segments (excluding the points on the line segment BF);
 the line segment PL is represented by coordinates (x, −0.1135x 2 +12.112x−280.43, 0.1135x 2 −13.112x+380.43), 
 the line segment MA′ is represented by coordinates (x, 0.0016x 2 −0.9473x+57.497, −0.0016x 2 −0.0527x+42.503), 
 the line segment A′B is represented by coordinates (x, 0.0029x 2 −1.0268x+58.7, −0.0029x 2 +0.0268x+41.3), 
 the line segment FT is represented by coordinates (x, 0.0078x 2 −0.7501x+61.8, −0.0078x 2 −0.2499x+38.2), 
 the line segment TP is represented by coordinates (x, 0.00672x 2 −0.7607x+63.525, −0.00672x 2 −0.2393x+36.475), and 
 the line segments LM and BF are straight lines. 
 
     
     
         14 . The refrigeration apparatus according to  claim 8 ,
 wherein   when the mass % of HFO-1132(E), HFO-1123, and R1234yf based on their sum in the refrigerant mixture 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 PL, LQ, QR, and RP that connect the following 4 points:   
       point P (55.8, 42.0, 2.2), 
       point L (63.1, 31.9, 5.0), 
       point Q (62.8, 29.6, 7.6), and 
       point R (49.8, 42.3, 7.9), 
       or on the above line segments;
 the line segment PL is represented by coordinates (x, −0.1135x 2 +12.112x−280.43, 0.1135x 2 −13.112x+380.43), 
 the line segment RP is represented by coordinates (x, 0.00672x 2 −0.7607x+63.525, −0.00672x 2 −0.2393x+36.475), and 
 the line segments LQ and QR are straight lines. 
 
     
     
         15 . The refrigeration apparatus according to  claim 8 ,
 wherein   when the mass % of HFO-1132(E), HFO-1123, and R1234yf based on their sum in the refrigerant mixture 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 SM, MA′, A′B, BF, FT, and TS that connect the following 6 points:   
       point S (62.6, 28.3, 9.1), 
       point M (60.3, 6.2, 33.5), 
       point A′ (30.6, 30.0, 39.4), 
       point B (0.0, 58.7, 41.3), 
       point F (0.0, 61.8, 38.2), and 
       point T (35.8, 44.9, 19.3), 
       or on the above line segments,
 the line segment MA′ is represented by coordinates (x, 0.0016x 2 −0.9473x+57.497, −0.0016x 2 −0.0527x+42.503), 
 the line segment A′B is represented by coordinates (x, 0.0029x 2 −1.0268x+58.7, −0.0029x 2 +0.0268x+41.3), 
 the line segment FT is represented by coordinates (x, 0.0078x 2 −0.7501x+61.8, −0.0078x 2 −0.2499x+38.2), 
 the line segment TS is represented by coordinates (x, −0.0017x 2 −0.7869x+70.888, −0.0017x 2 -0.2131x+29.112), and 
 the line segments SM and BF are straight lines. 
 
     
     
         16 . The refrigeration apparatus according to  claim 1 ,
 wherein   the refrigerant mixture comprises trans-1,2-difluoroethylene (HFO-1132(E)) and trifluoroethylene (HFO-1123) in a total amount of 99.5 mass % or more based on the entire refrigerant, and   the refrigerant mixture comprises 62.0 mass % to 72.0 mass % of HFO-1132(E) based on the entire refrigerant mixture.   
     
     
         17 . The refrigeration apparatus according to  claim 1 ,
 wherein   the refrigerant mixture comprises trans-1,2-difluoroethylene (HFO-1132(E)) and trifluoroethylene (HFO-1123) in a total amount of 99.5 mass % or more based on the entire refrigerant mixture, and   the refrigerant mixture comprises 45.1 mass % to 47.1 mass % of HFO-1132(E) based on the entire refrigerant mixture.   
     
     
         18 . The refrigeration apparatus according to  claim 1 ,
 wherein   the refrigerant mixture comprises trans-1,2-difluoroethylene (HFO-1132(E)), trifluoroethylene (HFO-1123), 2,3,3,3-tetrafluoro-1-propene (R1234yf), and difluoromethane (R32),   
       wherein
 when the mass % of HFO-1132(E), HFO-1123, R1234yf, and R32 based on their sum in the refrigerant mixture is respectively represented by x, y, z, and a, 
 if 0<a≤11.1, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), HFO-1123, and R1234yf is (100−a) mass % are within the range of a figure surrounded by straight lines GI, IA, AB, BD′, D′ C, and CG that connect the following 6 points: 
 
       point G (0.026a 2 −1.7478a+72.0, −0.026a 2 +0.7478a+28.0, 0.0), 
       point I (0.026a 2 −1.7478a+72.0, 0.0, −0.026a 2 +0.7478a+28.0), 
       point A (0.0134a 2 −1.9681a+68.6, 0.0, −0.0134a 2 +0.9681a+31.4), 
       point B (0.0, 0.0144a 2 −1.6377a+58.7, −0.0144a 2 +0.6377a+41.3), 
       point D′ (0.0, 0.0224a 2 +0.968a+75.4, −0.0224a 2 −1.968a+24.6), and 
       point C (−0.2304a 2 −0.4062a+32.9, 0.2304a 2 −0.5938a+67.1, 0.0), 
       or on the straight lines GI, AB, and D′C (excluding point G, point I, point A, point B, point D′, and point C);
 if 11.1<a≤18.2, coordinates (x,y,z) in the ternary composition diagram are within the range of a figure surrounded by straight lines GI, IA, AB, BW, and WG that connect the following 5 points: 
 
       point G (0.02a 2 −1.6013a+71.105, −0.02a 2 +0.6013a+28.895, 0.0), 
       point I (0.02a 2 −1.6013a+71.105, 0.0, −0.02a 2 +0.6013a+28.895), 
       point A (0.0112a 2 −1.9337a+68.484, 0.0, −0.0112a 2 +0.9337a+31.516), 
       point B (0.0, 0.0075a 2 −1.5156a+58.199, −0.0075a 2 +0.5156a+41.801), and 
       point W (0.0, 100.0−a, 0.0), 
       or on the straight lines GI and AB (excluding point G, point I, point A, point B, and point W);
 if 18.2<a≤26.7, coordinates (x,y,z) in the ternary composition diagram are within the range of a figure surrounded by straight lines GI, IA, AB, BW, and WG that connect the following 5 points: 
 
       point G (0.0135a 2 −1.4068a+69.727, −0.0135a 2 +0.4068a+30.273, 0.0), 
       point I (0.0135a 2 −1.4068a+69.727, 0.0, −0.0135a 2 +0.4068a+30.273), 
       point A (0.0107a 2 −1.9142a+68.305, 0.0, −0.0107a 2 +0.9142a+31.695), 
       point B (0.0, 0.009a 2 −1.6045a+59.318, −0.009a 2 +0.6045a+40.682), and 
       point W (0.0, 100.0−a, 0.0), 
       or on the straight lines GI and AB (excluding point G, point I, point A, point B, and point W);
 if 26.7<a≤36.7, coordinates (x,y,z) in the ternary composition diagram are within the range of a figure surrounded by straight lines GI, IA, AB, BW, and WG that connect the following 5 points: 
 
       point G (0.0111a 2 −1.3152a+68.986, −0.0111a 2 +0.3152a+31.014, 0.0), 
       point I (0.0111a 2 −1.3152a+68.986, 0.0, −0.0111a 2 +0.3152a+31.014), 
       point A (0.0103a 2 −1.9225a+68.793, 0.0, −0.0103a 2 +0.9225a+31.207), 
       point B (0.0, 0.0046a 2 −1.41a+57.286, −0.0046a 2 +0.41a+42.714), and 
       point W (0.0, 100.0−a, 0.0), 
       or on the straight lines GI and AB (excluding point G, point I, point A, point B, and point W); and
 if 36.7<a≤46.7, coordinates (x,y,z) in the ternary composition diagram are within the range of a figure surrounded by straight lines GI, IA, AB, BW, and WG that connect the following 5 points: 
 
       point G (0.0061a 2 −0.9918a+63.902, −0.0061a 2 −0.0082a+36.098, 0.0), 
       point I (0.0061a 2 −0.9918a+63.902, 0.0, −0.0061a 2 −0.0082a+36.098), 
       point A (0.0085a 2 −1.8102a+67.1, 0.0, −0.0085a 2 +0.8102a+32.9), 
       point B (0.0, 0.0012a 2 −1.1659a+52.95, −0.0012a 2 +0.1659a+47.05), and 
       point W (0.0, 100.0−a, 0.0), 
       or on the straight lines GI and AB (excluding point point I, point A, point B, and point W). 
     
     
         19 . The refrigeration apparatus according to  claim 1 ,
 wherein   the refrigerant mixture comprises trans-1,2-difluoroethylene (HFO-1132(E)), trifluoroethylene (HFO-1123), 2,3,3,3-tetrafluoro-1-propene (R1234yf), and difluoromethane (R32),   
       wherein
 when the mass % of HFO-1132(E), HFO-1123, R1234yf, and R32 based on their sum in the refrigerant mixture is respectively represented by x, y, z, and a, 
 if 0<a≤11.1, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), HFO-1123, and R1234yf is (100−a) mass % are within the range of a figure surrounded by straight lines JK′, K′B, BD′, D′C, and CJ that connect the following 5 points: 
 
       point J (0.0049a 2 −0.9645a+47.1, −0.0049a 2 −0.0355a+52.9, 0.0), 
       point K′ (0.0514a 2 −2.4353a+61.7, −0.0323a 2 +0.4122a+5.9, −0.0191a 2 +1.0231a+32.4), 
       point B (0.0, 0.0144a 2 −1.6377a+58.7, −0.0144a 2 +0.6377a+41.3), 
       point D′ (0.0, 0.0224a 2 +0.968a+75.4, −0.0224a 2 −1.968a+24.6), and 
       point C (−0.2304a 2 −0.4062a+32.9, 0.2304a 2 −0.5938a+67.1, 0.0), 
       or on the straight lines JK′, K′B, and D′C (excluding point J, point B, point D′, and point C);
 if 11.1<a≤18.2, coordinates (x,y,z) in the ternary composition diagram are within the range of a figure surrounded by straight lines JK′, K′B, BW, and WJ that connect the following 4 points: 
 
       point J (0.0243a 2 −1.4161a+49.725, −0.0243a 2 +0.4161a+50.275, 0.0), 
       point K′ (0.0341a 2 −2.1977a+61.187, −0.0236a 2 +0.34a+5.636,−0.0105a 2 +0.8577a+33.177), 
       point B (0.0, 0.0075a 2 −1.5156a+58.199, −0.0075a 2 +0.5156a+41.801), and 
       point W (0.0, 100.0−a, 0.0), 
       or on the straight lines JK′ and K′B (excluding point J, point B, and point W);
 if 18.2<a≤26.7, coordinates (x,y,z) in the ternary composition diagram are within the range of a figure surrounded by straight lines JK′, K′B, BW, and WJ that connect the following 4 points: 
 
       point J (0.0246a 2 −1.4476a+50.184, −0.0246a 2 +0.4476a+49.816, 0.0), 
       point K′ (0.0196a 2 −1.7863a+58.515, −0.0079a 2 -0.1136a+8.702, −0.0117a 2 +0.8999a+32.783), 
       point B (0.0, 0.009a 2 −1.6045a+59.318, −0.009a 2 +0.6045a+40.682), and 
       point W (0.0, 100.0−a, 0.0), 
       or on the straight lines JK′ and K′B (excluding point J, point B, and point W);
 if 26.7<a≤36.7, coordinates (x,y,z) in the ternary composition diagram are within the range of a figure surrounded by straight lines JK′, K′A, AB, BW, and WJ that connect the following 5 points: 
 
       point J (0.0183a 2 −1.1399a+46.493, −0.0183a 2 +0.1399a+53.507, 0.0), 
       point K′ (−0.0051a 2 +0.0929a+25.95, 0.0, 0.0051a 2 −1.0929a+74.05), 
       point A (0.0103a 2 −1.9225a+68.793, 0.0, −0.0103a 2 +0.9225a+31.207), 
       point B (0.0, 0.0046a 2 −1.41a+57.286, −0.0046a 2 +0.41a+42.714), and 
       point W (0.0, 100.0−a, 0.0), 
       or on the straight lines JK′, K′A, and AB (excluding point J, point B, and point W); and
 if 36.7<a≤46.7, coordinates (x,y,z) in the ternary composition diagram are within the range of a figure surrounded by straight lines JK′, K′A, AB, BW, and WJ that connect the following 5 points: 
 
       point J (−0.0134a 2 +1.0956a+7.13, 0.0134a 2 −2.0956a+92.87, 0.0), 
       point K′ (−1.892a+29.443, 0.0, 0.892a+70.557), 
       point A (0.0085a 2 −1.8102a+67.1, 0.0, −0.0085a 2 +0.8102a+32.9), 
       point B (0.0, 0.0012a 2 −1.1659a+52.95, −0.0012a 2 +0.1659a+47.05), and 
       point W (0.0, 100.0−a, 0.0), 
       or on the straight lines JK′, K′A, and AB (excluding point J, point B, and point W). 
     
     
         20 . The refrigeration apparatus according to  claim 1 ,
 wherein   the refrigerant mixture comprises 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 mixture 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 U, JN, NE, and EI that connect the following 4 points:   
       point I (72.0, 0.0, 28.0), 
       point J (48.5, 18.3, 33.2), 
       point N (27.7, 18.2, 54.1), and 
       point E (58.3, 0.0, 41.7), 
       or on these line segments (excluding the points on the line segment EI;
 the line segment U is represented by coordinates (0.0236y 2 −1.7616y+72.0, y, −0.0236y 2 +0.7616y+28.0); 
 the line segment NE is represented by coordinates (0.012y 2 −1.9003y+58.3, y, −0.012y 2 +0.9003y+41.7); and 
 the line segments JN and EI are straight lines. 
 
     
     
         21 . The refrigeration apparatus according to  claim 1 ,
 wherein   the refrigerant mixture comprises 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 mixture 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 MM′, M′N, NV, VG; and GM that connect the following 5 points: 
 
       point M (52.6, 0.0, 47.4), 
       point M′(39.2, 5.0, 55.8), 
       point N (27.7, 18.2, 54.1), 
       point V (11.0, 18.1, 70.9), and 
       point G (39.6, 0.0, 60.4), 
       or on these line segments (excluding the points on the line segment GM);
 the line segment MM′ is represented by coordinates (0.132y 2 −3.34y+52.6, y, −0.132y 2 +2.34y+47.4); 
 the line segment M′N is represented by coordinates (0.0596y 2 −2.2541y+48.98, y, −0.0596y 2 +1.2541y+51.02); 
 the line segment VG is represented by coordinates (0.0123y 2 −1.8033y+39.6, y, −0.0123y 2 +0.8033y+60.4); and 
 the line segments NV and GM are straight lines. 
 
     
     
         22 . The refrigeration apparatus according to  claim 1 ,
 wherein   the refrigerant mixture comprises 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 mixture 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 ON, NU, and UO that connect the following 3 points:   
       point O (22.6, 36.8, 40.6), 
       point N (27.7, 18.2, 54.1), and 
       point U (3.9, 36.7, 59.4), 
       or on these line segments;
 the line segment ON is represented by coordinates (0.0072y 2 −0.6701y+37.512, y, −0.0072y 2 −0.3299y+62.488); 
 the line segment NU is represented by coordinates (0.0083y 2 −1.7403y+56.635, y, −0.0083y 2 +0.7403y+43.365); and 
 the line segment UO is a straight line. 
 
     
     
         23 . The refrigeration apparatus according to  claim 1 ,
 wherein   the refrigerant mixture comprises 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 mixture 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 QR, RT, TL, LK, and KQ that connect the following 5 points:   
       point Q (44.6, 23.0, 32.4), 
       point R (25.5, 36.8, 37.7), 
       point T (8.6, 51.6, 39.8), 
       point L (28.9, 51.7, 19.4), and 
       point K (35.6, 36.8, 27.6), 
       or on these line segments;
 the line segment QR is represented by coordinates (0.0099y 2 −1.975y+84.765, y, −0.0099y 2 +0.975y+15.235); 
 the line segment RT is represented by coordinates (0.0082y 2 −1.8683y+83.126, y, −0.0082y 2 +0.8683y+16.874); 
 the line segment LK is represented by coordinates (0.0049y 2 −0.8842y+61.488, y, −0.0049y 2 −0.1158y+38.512); 
 the line segment KQ is represented by coordinates (0.0095y 2 −1.2222y+67.676, y, −0.0095y 2 +0.2222y+32.324); and 
 the line segment TL is a straight line. 
 
     
     
         24 . The refrigeration apparatus according to  claim 1 ,
 wherein   the refrigerant mixture comprises 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 mixture 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 PS, ST, and TP that connect the following 3 points:   
       point P (20.5, 51.7, 27.8), 
       point S (21.9, 39.7, 38.4), and 
       point T (8.6, 51.6, 39.8), 
       or on these line segments;
 the line segment PS is represented by coordinates (0.0064y 2 −0.7103y+40.1, y, −0.0064y 2 −0.2897y+59.9); 
 the line segment ST is represented by coordinates (0.0082y 2 −1.8683y+83.126, y, −0.0082y 2 +0.8683y+16.874); and 
 the line segment TP is a straight line. 
 
     
     
         25 . The refrigeration apparatus according to  claim 1 ,
 wherein   the refrigerant mixture comprises 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 mixture 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 IK, KB′, B′H, HR, RG, and GI that connect the following 6 points:   
       point I (72.0, 28.0, 0.0), 
       point K (48.4, 33.2, 18.4), 
       point B′ (0.0, 81.6, 18.4), 
       point H (0.0, 84.2, 15.8), 
       point R (23.1, 67.4, 9.5), and 
       point G (38.5, 61.5, 0.0), 
       or on these line segments (excluding the points on the line segments B′H and GI);
 the line segment IK is represented by coordinates (0.025z 2 −1.7429z+72.00, −0.025z 2 +0.7429z+28.0, z), 
 the line segment HR is represented by coordinates (−0.3123z 2 +4.234z+11.06, 0.3123z 2 −5.234z+88.94, z), 
 the line segment RG is represented by coordinates (−0.0491z 2 −1.1544z+38.5, 0.0491z 2 +0.1544z+61.5, z), and 
 the line segments KB′ and GI are straight lines. 
 
     
     
         26 . The refrigeration apparatus according to  claim 1 ,
 wherein   the refrigerant mixture comprises 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 mixture 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 IJ, JR, RG, and GI that connect the following 4 points:   
       point I (72.0, 28.0, 0.0), 
       point J (57.7, 32.8, 9.5), 
       point R (23.1, 67.4, 9.5), and 
       point G (38.5, 61.5, 0.0), 
       or on these line segments (excluding the points on the line segment GI);
 the line segment U is represented by coordinates (0.025z 2 −1.7429z+72.0, −0.025z 2 +0.7429z+28.0, z), 
 the line segment RG is represented by coordinates (−0.0491z 2 −1.1544z+38.5, 0.0491z 2 +0.1544z+61.5, z), and 
 the line segments JR and GI are straight lines. 
 
     
     
         27 . The refrigeration apparatus according to  claim 1 ,
 wherein   the refrigerant mixture comprises 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 mixture 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 MP, PB′, B′H, HR, RG, and GM that connect the following 6 points:   
       point M (47.1, 52.9, 0.0), 
       point P (31.8, 49.8, 18.4), 
       point B′ (0.0, 81.6, 18.4), 
       point H (0.0, 84.2, 15.8), 
       point R (23.1, 67.4, 9.5), and 
       point G (38.5, 61.5, 0.0), 
       or on these line segments (excluding the points on the line segments B′H and GM);
 the line segment MP is represented by coordinates (0.0083z 2 −0.984z+47.1, −0.0083z 2 -0.016z+52.9, z), 
 the line segment HR is represented by coordinates (−0.3123z 2 +4.234z+11.06, 0.3123z 2 −5.234z+88.94, z), 
 the line segment RG is represented by coordinates (−0.0491z 2 −1.1544z+38.5, 0.0491z 2 +0.1544z+61.5, z), and 
 the line segments PB′ and GM are straight lines. 
 
     
     
         28 . The refrigeration apparatus according to  claim 1 ,
 wherein   the refrigerant mixture comprises 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 mixture 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 MN, NR, RG, and GM that connect the following 4 points:   
       point M (47.1, 52.9, 0.0), 
       point N (38.5, 52.1, 9.5), 
       point R (23.1, 67.4, 9.5), and 
       point G (38.5, 61.5, 0.0), 
       or on these line segments (excluding the points on the line segment GM);
 the line segment MN is represented by coordinates (0.0083z 2 −0.984z+47.1, −0.0083z 2 −0.016z+52.9, z), 
 the line segment RG is represented by coordinates (−0.0491z 2 −1.1544z+38.5, 0.0491z 2 +0.1544z+61.5, z), and 
 the line segments JR and GI are straight lines. 
 
     
     
         29 . The refrigeration apparatus according to  claim 1 ,
 wherein   the refrigerant mixture comprises 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 mixture 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 PS, ST, and TP that connect the following 3 points:   
       point P (31.8, 49.8, 18.4), 
       point S (25.4, 56.2, 18.4), and 
       point T (34.8, 51.0, 14.2), 
       or on these line segments;
 the line segment ST is represented by coordinates (−0.0982z 2 +0.9622z+40.931, 0.0982z 2 −1.9622z+59.069, z), 
 the line segment TP is represented by coordinates (0.0083z 2 −0.984z+47.1, −0.0083z 2 −0.016z+52.9, z), and 
 the line segment PS is a straight line. 
 
     
     
         30 . The refrigeration apparatus according to  claim 1 ,
 wherein   the refrigerant mixture comprises 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 mixture 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 QB″, B″D, DU, and UQ that connect the following 4 points:   
       point Q (28.6, 34.4, 37.0), 
       point B″ (0.0, 63.0, 37.0), 
       point D (0.0, 67.0, 33.0), and 
       point U (28.7, 41.2, 30.1), 
       or on these line segments (excluding the points on the line segment B″D);
 the line segment DU is represented by coordinates (−3.4962z 2 +210.71z−3146.1, 3.4962z 2 −211.71z+3246.1, z), 
 the line segment UQ is represented by coordinates (0.0135z 2 −0.9181z+44.133, −0.0135z 2 −0.0819z+55.867, z), and 
 the line segments QB″ and B″D are straight lines.