A tube-fin three-fluid heat exchanger is
developed to achieve good coupling performance of mechanical
refrigeration and thermosyphon as shown in Fig. 2. The inner tube
is inserted into the outer tube with plat fins outside. The tubes are
connected by bend tubes to construct flow circuits. Refrigeration
fluid flows inside the inner tube and is divided into 4 circuits.
Thermosyphon fluid flows inside the annular channel between the
inner tube and the outer tube and is divided into 28 circuits. Air
flows outside the outer tube through the fins. A parallel flow
evaporator is designed for the thermosyphon loop. The specifications
of the three-fluid heat exchanger and the evaporator are listed
in Table 1.