Behaviours of flow and flow-induced noise generated from leading bogie region of high-speed train using flow-through cowcatcher

• The flow-through cowcatcher suppresses flow separation and promotes stable vortex evolution in the bogie cavity, reducing high-amplitude wall pressure fluctuations by up to 40%. • Far-field sound pressure levels decrease by 0.4–0.6 dB(A) with the flow-through cowcatcher, as validated by semi-anechoic wind tunnel experiments. • The dominant sound source around the leading bogie region is shrunk with intensity reduced by about 1.0 dB(A), confirming effective aerodynamic noise mitigation. • The study provides theoretical insight and engineering guidance for low-noise design of high-speed train nose cars.