无导叶对转涡轮三维流场的非定常数值模拟

为了揭示1 1／2(无低压导叶)对转涡轮流场的非定常流动特性,运用全三维粘性流场计算程序对某1 1／2对转涡轮模型级的流场进行了非定常数值模拟。结果表明,非定常计算可以获得比定常计算更为丰富的流场信息;非定常效应具有逐级累积的趋势;高压导叶压力面叶表静压展向分布比吸力面均匀;高低压动叶压力面和吸力面叶表静压的展向分布不均匀;高压动叶的负荷随叶高的增加而增大;高低压动叶出口气流角沿整个叶展均较大地偏离轴向,说明高低压涡轮的功负荷较高,在出功量上达到了设计目标。

NUMERICAL ANALYSIS OF 3-D UNSTEADY FLOW IN A VANELESS COUNTER-ROTATING TURBINE

In order to reveal the unsteady flow characteristics on a Vaneless Counter-Rotating Turbine (VCRT), a three-dimensional, viscous, unsteady CFD analysis was performed. Results show that unsteady simulation is superior to steady simulation because more flow characteristics can be obtained by unsteady simulation. The unsteady effects in upstream airfoil rows are weaker than those in downstream airfoil rows in the VCRT. The static pressure distribution along the span in the pressure surface of the HPS (high pressure stator) is more uniform than that in the suction surface. The static pressure distributions along the span in the pressure surfaces and the suction surfaces of the HPR (high pressure rotor) and LPR (low pressure rotor) are all uneven. The numerical results also indicate that the load of the HPR will increase with the increase of the span. And the deviations are very big between the outlet flow angles of the HPR and the LPR and the axial direction. It indicates that the specific work of the HPR and the LPR is enough to reach the design objective.