The big
issue of S-CO2 Brayton cycle is to develop compact heat exchanger which is
comparable to the size of turbines and compressors. One of the candidates of
this compact heat exchanger is printed circuit heat exchanger (PCHE). PCHE is
manufactured by chemical etching and diffusion bonding technologies (Fig. 14).
Using these two technologies, PCHE has many micro-scale channels and durability
to high pressure and temperature. Further, it has larger heat transfer area per
volume than other conventional heat exchanger. However, its performance is
greatly affected by the channel shapes. Thus, it is important to develop
efficient and processible channel shape of PCHE. Recently, diverse heat
exchangers also can be suggested and studied for the purpose of S-CO2 Brayton
cycle as well as the PCHE.