:To achieve a stable addition of foaming agent under high flow rates, an independently designed Venturi structure with self-suction of liquid and foaming agent was numerically simulated. We simulated the effects of different suction structure diameters, contraction angles, throat length and position on the suction ratio, compared and analyzed the data, and determined the optimal suction structure parameters. The suction ratio stabilizes and then decreases as the outlet pressure increases. At an outlet pressure of 0.48 MPa, the suction ratio remains stable at 1.14%. However, as the outlet pressure increases, the ability of the Venturi structure to add foaming agent to the self-suction liquid decreases under high flow rates, causing the suction ratio to rapidly decrease to a minimum value of 0.55 MPa. The suction ratio shows a tendency to first stabilize and then decrease as the outlet pressure increases. When the outlet pressure reaches 0.48 MPa, the suction ratio can remain stable at 1.14%; as the outlet pressure increases, the addition ability of the Venturi structure with foaming agent added to the self-suction liquid under high flow rate decreases, and the suction ratio rapidly decreases to a minimum value of 0.55 MPa. We have conducted a detailed analysis of the process and flow field of liquid suction. As the pressure ratio increases, the high-speed area of the throat gradually shrinks, and the flow field in the diffusion section fluctuates. When the outlet pressure is 0.6 MPa and the velocity field shifts towards the upper part of the diffusion section, the cavitation area will gradually disappear and lose its liquid suction ability.