Abstract:Two centrifugal molten salt pumps with single- and double-volute were designed under the same operating condition. Then, transient flow fields within two pumps were simulated and the tempe-rature distribution in the rotor was analyzed by using ANSYS to clarify the influence of volute structure on operational stability when the pumps transporting high-temperature molten salt. The stress, defor-mation and vibration mode were analyzed by employing fluid-thermal-structure coupling method after the calculated flow and temperature fields had been simultaneously applied to the rotor. The results indicate that the pressure load on blades is relieved and the axis-symmetry of the pressure distribution is improved within the double volute. The maximum deformation in the impeller and shaft is relatively large but also depends on shaft rotational angle significantly within the single-volute. Compared with the single-volute, the maximum equivalent stress in the impeller in the double-volute is larger, ho-wever, the maximum equivalent stress in the shaft is at a lower level. The rotor can meet the requirements of structural strength in the flow fields with two volutes under normal operating conditions.