Influence of Mainstream Turbulence Intensity on Heat Transfer Characteristics of a HP Turbine Stage With Inlet Hot Streak
Influence of Mainstream Turbulence Intensity on Heat Transfer Characteristics of a HP Turbine Stage With Inlet Hot Streak
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DOI：
10.1115/gt2015-42593
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发表时间：
2015-06
期刊：
影响因子：
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通讯作者：
Zhiduo Wang;Zhaofang Liu;Z. Feng
中科院分区：
文献类型：
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作者：
Zhiduo Wang;Zhaofang Liu;Z. Feng
对GE-E3高压涡轮机进行了非定常计算研究，在进口湍流度为5%、10%和20%时，在两个周向位置（相对于导叶前缘有冲击和无冲击）均出现进口热斑，分析了湍流和热斑的相互影响。对与γ-θ转捩模型耦合的剪切应力输运（SST）湍流模型的传热预测能力进行了验证研究。分析了涡轮机通道内湍流的衰减机理，并采用时均绝热壁温和换热系数（HTC）对翼型的换热特性进行了研究。结果表明，来流湍流度的增加，总体上有利于涡轮机的温度分布，特别是在非冲击工况和来流湍流度从10%增加到20%的情况下，叶片和叶顶表面的温度分布更为明显。虽然叶片和叶片表面的面积平均温度几乎没有变化，最大面积平均温度下降8.9 K诱导在尖端表面。在较高的湍流度下，在叶片、叶片压力面和吸力面中部区域观察到较高的HTC。然而，在叶片吸力面和叶尖端壁区域的热负荷对湍流效应不敏感，因此，当来流湍流强度增加时，这些区域的热负荷不是关键的。HS位置不仅影响翼型表面温度变化，而且由于流体驱动温度的变化，也会轻微影响叶片和叶片中跨HTC。Copyright © 2015 by ASME
An unsteady computational study were carried out for the GE-E3 HP turbine at inflow turbulence intensities of 5%, 10% and 20% accompanying with inlet hot streak (HS) at two circumferential positions (impinging and non-impinging relative to vane leading edge) to analyze the interacted turbulence and HS influences. Several validation studies were performed to investigate the heat transfer prediction ability of shear stress transport (SST) turbulence model coupled with γ-θ transition model. Turbulence decay mechanisms in turbine passage were presented, and the airfoil heat transfer behaviors were explored by means of both time-averaged adiabatic wall temperature and heat transfer coefficient (HTC). The results indicate that increase of inflow turbulence leads to favorable turbine temperature distributions in general, and on the blade and tip surface in particular, especially for the non-impinging case and inflow turbulence increasing from 10% to 20%. While the vane and blade surface area-averaged temperatures are hardly changed, a maximum area-averaged temperature drop of 8.9 K is induced at the tip surface. Higher HTC is observed at vane, blade pressure surface, and suction surface mid region at higher turbulence. However, HTCs at endwall regions of blade suction surface and blade tip are insensitive to the turbulence effect, thus the heat load of these regions is not critical when the inflow turbulence intensity is increased. HS position not only affects the airfoil surface temperature variations, but also slightly affects the vane and blade midspan HTC for the variation of fluid driving temperature.Copyright © 2015 by ASME