Investigation on matching characteristics of nuclear main pump guide vanes and annular casing

Based on the RNG k–ɛ turbulence model, the multi-coordinate system is used to simulate the three-dimensional unsteady constant value of the nuclear main pump model under different axial and circumferential positions of the guide vane and the annular casing. By analyzing the external characteristics, pressure field and velocity field of different schemes and comparing the pressure pulsation at the impeller outlet, the flow of guide vane and the annular casing is studied through the axial and circumferential position changes in the vane and the annular casing. The results show that the axial distance between the center line of the guide vane and the center line of the outlet extension will increase the uneven distribution of pressure in the impeller outlet and the annular casing and the circumferential position of the guide vane will increase as well. When the center lines of the two are coincident, the pressure distribution in the impeller outlet and the casing is relatively uniform. The change in the axial and circumferential positions of the guide vane of the nuclear main pump has little effect on the vector distribution of the impeller outlet flow, and the influence of liquid flow in the interior of casing is large. The impeller outlet pressure pulsation increases as the axial distance between the guide vane outlet center line and the annular casing outlet center line increases. When the two center lines coincide, the impeller outlet pressure pulsation peak is the lowest.