Effects of Heat Transfer Characteristics of R32 and R1234yf with Al₂O₃ Nanoparticle through U-Bend Tube Evaporator

Figure 19

Flow formation for R1234yf and vapor quality within 0.01∼0.74 occurred before the bend (x = 0.01 to 0.41), at the bend (x = 0.51 to 0.61), and after the bend (x = 0.68 to 0.74) at the mass flux of 160 kg/m²·s and at temperature of 350 K.