Fluid–structure interaction characteristics between stator–rotor clearance flow and rotor of full tubular pump

Affected by the hydrodynamic pressure difference between the inlet and outlet side of the impeller of a full tubular pump (FTP), stator–rotor clearance flow inevitably exists during the operation of FTP, disturbing the flow field and causing hydraulic friction around the rotor. Based on the fluid–solid interaction method, this paper explored the interaction characteristics between the flow field of the stator–rotor clearance flow and the rotor structure. By conducting numerical simulation and model test, the deformation and stress distribution characteristics of the rotor were investigated and its high-strength stress region was located, where the alteration mechanism of the stator–rotor clearance vortex and the spatiotemporal distribution of velocity field were further deduced. The results show that during the operation of FTP, the maximum deformation region of the rotor was concentrated in the outer ring which showed obvious periodicity and the peak equivalent stress of the rotor was distributed along the bone line of the impeller with the span of 0.1. With the widening of spacing between the stator and the rotor, the accumulation of high momentum fluid both near the stator wall and the rotor wall was increased, and the radial non-uniformity of the clearance flow circulation was aggravated so that part of the mainstream water in the intersection domain deflected inward, magnifying the blade stress and leading to the peak deformation surface of the rotor twirling along the direction of impeller rotation at the speed of 8°/mm. This study investigated the fluid–structure interaction features of FTP, providing reference for future research on performance optimization.