Abstract—This study presents a three-stage optimisation framework designed for the dynamic performance enhancement of a shipboard horizontal canned-motor pump. The framework integrates high-fidelity Finite Element (FE) modelling, experimental modal validation, and topologyoptimisation- based structural redesign, considering realistic installation constraints. A comprehensive whole-pump model, accounting for actual mounting conditions, is developed, and a strategy combining stiffening, lightweighting, and reinforcement is implemented to reduce structural mass while improving dynamic performance. The model’s accuracy is validated through impact-hammer modal tests, with the first six natural frequencies predicted within 2% of experimental values. Modal analysis identifies a low-frequency global–high-frequency local vibration pattern, with deformation predominantly in the base transition, flange, and outlet regions. Following optimisation, the first natural frequency increases from 42.31 Hz to 76.86 Hz, and higher-order modes increase by approximately 18%, leading to more uniform mode shapes and reduced local vibration. This framework offers valuable insights for vibration mitigation and lightweight structural redesign of shipboard rotating machinery. However, internal fluid– structure interaction within the canned motor and ship-hull foundation flexibility are not incorporated in the current model, and these factors may influence low-order modal characteristics and the applicability of the results under realworld operating conditions. Future research will incorporate Fluid–Structure Interaction (FSI) modelling and shipboard experimental validation to further assess the robustness and engineering applicability of the proposed framework.

Keywords—shipboard canned-motor pump, installationconstrained optimisation, modal-topology co-design, highfidelity Finite Element (FE) modelling, frequency-separation enhancement

Cite: Xiang Sun, Duo Yang, Mingyan Shi, Gaoce Tan, Taomin Song, and Panhao Yang, "Modal Analysis-Informed Topology Optimization for Dynamic Performance Enhancement of Horizontal Canned Motor Pumps," International Journal of Mechanical Engineering and Robotics Research, Vol. 15, No. 2, pp. 145-155, 2026. doi: 10.18178/ijmerr.15.2.145-155

Copyright © 2026 by the authors. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).