Particle deposition characteristics in printed circuit heat exchanger

High tempera ture gas cooled reactor coupled helium turbine cycle is an important potential application of advanced nuclear energy. Among cycle system, the printed circuit heat exchanger with microchannel (1~2 mm) is the key heat exchange equipment of system However, the dust particles generated in the reactor are easy to deposit on the surface of printed circuit heat exchanger due to micro channel and channel steering. The deposition of dust particle will affect its heat transfer efficiency and may cause the block of micro channels of the printed circuit heat exchanger. Therefore, it is of great significance to evaluate the influence of deposition of dust particles on micro channels heat exchangers under long term operation. This study used near wall drag model to cons ider shear flow in the PCHE and EA rebound model to determine particle deposition on the channel. A dynamic mesh method is used to consider long term particle deposition morphology. The results show that deposition fraction of particles increases first and then decreases with the increase of particle size. For deposition distribution, s mall particle sizes mainly deposit on the upstream bend channel of PCHE. As the deposition loss, the downstream particle deposition amount significantly decreases. For large particle sizes, sufficient kinetic energy needs to be lost before deposition occurring, resulting in a more pronounced deposition distribution downstream. (authors)