The vortex-induced vibration (VIV) phenomenon of crossed cylinders at high Reynolds numbers is investigated through numerical simulation, focusing on its application in energy capture. The accuracy of the established numerical model is first validated by comparing it with experimental data from existing literature. Subsequently, the VIV of the crossed cylinder is simulated and compared with that of a standard cylinder. It is observed that the vibration frequency of the crossed cylinder consistently remains lower than that of the standard cylinder across all flow velocities. Additionally, the presence of the vertical cylinder results in a decrease in vortex intensity for the cross cylinder at low and medium flow rates, leading to reduced amplitude at low flow rates and an increase in the starting flow rate. In the middle velocity range, there is an increase in amplitude due to changes in vortex shedding position. At high velocity ranges, there are no significant changes in vortex intensity or shedding position, with amplitudes similar to those of a standard cylinder. Finally, the study investigated the vortex vibration response of a crossed cylinder under varying mass ratios and spring stiffnesses, elucidating the significant influence of both parameters on the lock-in range and amplitude.