An investigation on the ventral diverterless high offset S-shaped inlet is carried out at Mach numbers from 0.600 to 1.534, angles of attack from -4° to 9.4°, and yaw angles from 0° to 8°. Results ...An investigation on the ventral diverterless high offset S-shaped inlet is carried out at Mach numbers from 0.600 to 1.534, angles of attack from -4° to 9.4°, and yaw angles from 0° to 8°. Results indicate： （1） a large region of low total pressure exists at the lower part of the inlet exit caused by the counter-rotating vortices in the S-shaped duct; （2） the performances of the inlet at Mach number 1.000 reach almost the highest, so the propulsion system could work efficiently in terms of aerodynamics; （3） the total pressure recovery increases slowly at first and then remains unvaried as the Mach number rises from 0.6 to 1.0, however, it does in an opposite manner in the conventional diverter-equipped S-shaped inlet; （4） the performances of the inlet are generally insensitive to angles of attack from -4° to 9.4° and yaw angles from 0° to 8° at Mach number 0.850, and angles of attack from -2° to 6° and yaw angles from 0° to 5° at Mach number 1.534.展开更多
The heat transfer in a novel smooth wedge-shaped cooling channel with lateral ejection of turbine blade trailing edge is experimentally investigated in both non-rotating and rotating cases.Beside the conventional inle...The heat transfer in a novel smooth wedge-shaped cooling channel with lateral ejection of turbine blade trailing edge is experimentally investigated in both non-rotating and rotating cases.Beside the conventional inlet at the bottom of the channel, an extra coolant injection from 8 lateral non-equant holes is introduced to improve the overall heat transfer. The total mass flow rate ratio（lateral mass flow rate/total mass flow rate） varies from 0 to 1.0. The major inlet Reynolds number and rotation number respectively vary from 10000 to 20000 and from 0 to 1.16. Experimental results show that the lateral inlet decreases local bulk temperature and increases local heat transfer at the middle and the top of the static channel. In rotating cases, the lateral inlet notably improves the heat transfer at the high-radius half channel and compensates the negative effects induced by the rotation. Both intensity and uniformity of heat transfer inside the channel are enhanced while flow resistance decreases with proper mass flow rate ratio of coolant from two inlets. The most satisfactory total mass flow rate ratio is around 2/3. This new structural style of cooling channel has huge potential and provides new direction of heat transfer of turbine blade trailing edge.展开更多
基金National Basic Research Program of China (5130802)
文摘An investigation on the ventral diverterless high offset S-shaped inlet is carried out at Mach numbers from 0.600 to 1.534, angles of attack from -4° to 9.4°, and yaw angles from 0° to 8°. Results indicate： （1） a large region of low total pressure exists at the lower part of the inlet exit caused by the counter-rotating vortices in the S-shaped duct; （2） the performances of the inlet at Mach number 1.000 reach almost the highest, so the propulsion system could work efficiently in terms of aerodynamics; （3） the total pressure recovery increases slowly at first and then remains unvaried as the Mach number rises from 0.6 to 1.0, however, it does in an opposite manner in the conventional diverter-equipped S-shaped inlet; （4） the performances of the inlet are generally insensitive to angles of attack from -4° to 9.4° and yaw angles from 0° to 8° at Mach number 0.850, and angles of attack from -2° to 6° and yaw angles from 0° to 5° at Mach number 1.534.
文摘The heat transfer in a novel smooth wedge-shaped cooling channel with lateral ejection of turbine blade trailing edge is experimentally investigated in both non-rotating and rotating cases.Beside the conventional inlet at the bottom of the channel, an extra coolant injection from 8 lateral non-equant holes is introduced to improve the overall heat transfer. The total mass flow rate ratio（lateral mass flow rate/total mass flow rate） varies from 0 to 1.0. The major inlet Reynolds number and rotation number respectively vary from 10000 to 20000 and from 0 to 1.16. Experimental results show that the lateral inlet decreases local bulk temperature and increases local heat transfer at the middle and the top of the static channel. In rotating cases, the lateral inlet notably improves the heat transfer at the high-radius half channel and compensates the negative effects induced by the rotation. Both intensity and uniformity of heat transfer inside the channel are enhanced while flow resistance decreases with proper mass flow rate ratio of coolant from two inlets. The most satisfactory total mass flow rate ratio is around 2/3. This new structural style of cooling channel has huge potential and provides new direction of heat transfer of turbine blade trailing edge.
文摘边界层吸入(BLI,boundary layer ingestion)式风扇进口存在复杂的畸变流场,现有研究大多局限于传统的三维模拟方式,计算耗时长。本文以DGEN380风扇转子为研究对象,设计了一款与之匹配的S型进气道以吸入来流边界层,并采用基于体积力模型(BFM,body force modelling)的计算方法,计算结果的参数变化趋势与非定常计算结果吻合良好,风扇入口的旋流角及无量纲总压值的周向均值与非定常结果偏差在6%以内,计算时间为非定常方法的1/50。基于此模型探究了15%、30%、60%进口高度下3种不同厚度BLI对于风扇转子进出口流场的影响。结果表明:针对风扇转子入口,在不同叶高处总压畸变及旋流畸变程度随着BLI厚度的增加均有所增加,且旋流分布呈现对涡形式,在经过风扇转子通道叶片作用之后,对涡逐渐转化为单向涡,风扇转子出口气流落后角减小,BLI区风扇功系数值较均匀流工况有所提升。
