为准确评估船舶汽轮机调节阀在低工况下的运行安全性，本研究旨在系统揭示宽频涡激振动与阀体结构间的流固耦合机理，并评估其共振风险，为振动抑制提供理论依据。为此，基于Ansys谐响应分析模块，结合模态叠加法开展谐响应分析，系统研究调节阀在宽频涡激振动下的流固耦合响应特性与共振机理。通过瞬态流场模拟获取流固耦合作用面的非定常流体激励力，基于调节阀结构模态分析结果，将不同工况下的流体激励力经快速傅里叶变换为频域载荷后施加至结构表面，实现了宽频激励下调节阀结构的谐响应特性分析。结果表明：在低开度下，阀瓣近壁面区域存在多处交替变换的旋涡结构，其产生的宽频涡流激振是诱发结构振动的主要因素；调节阀阀杆及阀瓣的固有频率远低于阀体固有频率，且阀杆前六阶模态与流体激励的主要频带（20–200 Hz）高度重合，存在显著的共振风险；进一步谐响应分析表明，阀杆振动响应随开度变化呈现显著差异：9.5%小开度下呈现多模态共振特征，而17.5%开度下则表现为基频主导型响应，揭示了不同流动形态对结构振动模式的调制作用。

To accurately assess the operational safety of marine steam turbine regulating valves under low-load conditions, this study aims to systematically reveal the fluid-structure interaction mechanism between broadband vortex-induced vibrations and the valve structure, and to evaluate the associated resonance risk, thereby providing a theoretical basis for vibration suppression. For this purpose, harmonic response analysis was conducted using the Ansys harmonic response module combined with the modal superposition method, to systematically investigate the fluid-structure interaction response characteristics and resonance mechanisms of the regulating valve under broadband vortex-induced vibrations. Unsteady fluid excitation forces at the fluid-structure interfaces were obtained through transient flow field simulations. Based on the structural modal analysis results, these forces under different working conditions were converted into frequency-domain loads via Fast Fourier Transform (FFT) and applied to the structural surface, enabling harmonic response analysis of the regulating valve structure under broadband excitation. The results indicate that at low openings, multiple alternating vortex structures near the valve disc surface generate broadband vortex-induced vibrations, which constitute the primary factor exciting structural vibrations. The natural frequencies of the valve stem and disc are significantly lower than those of the valve body, and the first six-order modal frequencies of the valve stem show high coincidence with the main fluid excitation frequency band (20–200 Hz), indicating a significant resonance risk. Further harmonic response analysis reveals substantial differences in the valve stem's vibration response with varying opening degrees: at 9.5% opening, it exhibits multi-modal resonance characteristics, whereas at 17.5% opening, it demonstrates a fundamental frequency-dominated response pattern, revealing the modulation effect of different flow patterns on structural vibration modes.

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