Abstract: The heat receiver is a key part of Solar Dynamic Power System. The structural parameter affects the heat transfer of the heat receiver. The enthalpy method was used to calculate the three-dimensional phase change process of the heat exchange tube. The maximum canister temperature, average canister temperature, the receiver gas exit temperature and liquid PCM fraction in many kinds of length diameter ratio and aperture were calculated. The results showed that the output temperature of the gas from the working fluid tubes could meet the expected demand during the sunlight and eclipse period. The maximum temperature of the PCM container was within the safe range.