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利用商用软件数值模拟了5个不同动叶稠度的轴流涡轮基元级的非定常流动情况,以研究动叶稠度对轴流涡轮基元级性能和流动情况的影响.通过对动叶稠度对基元级反力度、叶片进出口气流角、转子和静子中的流场及损失影响情况的考察研究,发现动叶稠度的改变对涡轮基元性能和流动情况的影响与静叶稠度存在重要关系.静叶稠度不变时,动叶稠度的改变通过影响流过涡轮基元级的流量来使基元级的反力度发生变化.当动叶稠度过大时,气流在转子中会过度膨胀加速而产生激波损失及其与附面层干涉形成的流动分离损失.动叶稠度过小时,转子进口会出现极大的正攻角致使动叶吸力面发生大范围的流动分离.静叶稠度一定时,存在一个最佳的动叶稠度,使涡轮基元级呈现最好的性能.
Numerical simulations of unsteady flow at the elemental level of five axial-flow turbines with different blade configurations were carried out by using commercial software to study the effect of blade consistency on the performance and flow of the axial-flow turbine at the element level. Elemental reaction force, the inlet and outlet airflow angles of the blades, the flow field and the influence of the loss on the rotors and stators. It is found that the influence of the change of blade consistency on the performance and flow conditions of the turbine impeller has an important relationship with the static blade consistency When the consistency of vane is constant, the change of blade consistency will change the velocity of elemental level by influencing the flow through the turbine element.When the consistency of the blade is too high, the flow will accelerate and expand excessively in the rotor And the loss of shock wave and the flow separation loss caused by the interference with the coating.When the consistency of the moving blade is too small, there will be a great positive angle of attack on the rotor inlet, resulting in a large range of flow separation on the suction surface of the rotor blade. Timing, there is an optimum bucket consistency that gives the best performance at the turbine stage.