Abstract:In order to reduce the required inletoutlet pressure difference of Venturi injector and improve the injection efficiency, adopting orthogonal design method, seven key structural parameters of Venturi injector were chosen to build eighteen structural parameter schemes, which were simulated by CFD technology and analyzed. Taking injection efficiency as an evaluation index, a most optimal structure combination was put forward and a sample was accordingly made and compared with the primary injector in this regard. Results showed that, when inlet pressure was kept constant, the injection flow rate of Venturi injector increased as the inletoutlet pressure difference expanded. For a given injection flow rate, a larger pressure difference was required as inlet pressure increased. Injection flow rate had an average increase of 1146%, and the maximum injection flow rate had an average increase of 315% after optimizing structural parameters. Under different inlet pressures, when starting injection, the critical pressure ratio of outlet pressure to inlet pressure was almost kept a constant value. For parameters before and after optimization, the average value of critical pressure ratio increased from 046 to 061, which indicated that the working pressure range of Venturi injector had been enlarged after optimization, and verified the reliability of structural optimization design and numerical simulation.
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