【摘要】 为了降低文丘里施肥器进出口压差和提高吸肥效率,选取文丘里施肥器的7个关键参数,采用正交设计方法构造了18种结构参数方案.应用CFD技术模拟分析了每种方案的吸肥性能,以吸肥效率为评价指标提出了最优结构参数方案,并加工成样品,与优化前产品进行了吸肥性能试验对比.结果表明:进口压力不变时,文丘里施肥器吸肥流量随着进出口压差的增大而增大;当吸肥流量相同时,进口压力越大,则所需的压差越大.优化后的吸肥流量较优化前平均提高了114.6%,最大吸肥流量平均提高了31.5%.不同的进口压力下,文丘里施肥器开始吸肥时临界压力比几乎是定值,优化前后平均值分别为0.46和0.61,表明结构优化后文丘里施肥器的工作压力范围得到了拓宽,验证了结构优化设计和数值模拟的可靠性.更多还原

【Abstract】 In order to reduce the required inlet-outlet 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 inlet-outlet 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 114.6%,and the maximum injection flow rate had an average increase of 31.5% 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 0.46 to 0.61,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.更多还原