|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Adjoint-Based Geometrically Constrained Aerodynamic Optimization of a Transonic Compressor Stage显示文摘Efficient method to handle the geometric constraints in the optimization of turbomachinery blade profile is required. Without constraints on the blade thickness, optimal designs typically yield thinner blade to reduce the friction loss, however, at the risk of degraded strength and stiffness. This issue is seldom discussed and existing literature always treat the blade thickness constraint in an indirect manner. In this work, two different geometric constraints on the blade thickness are proposed and applied in the adjoint optimization: one is on the maximum blade thickness and the other is on the blade area. Methods to compute sensitivities of both constraints are proposed and they are integrated into an optimization system based on a finite volume code and a solver for the discrete adjoint equation. Adjoint optimization is conducted to minimize the entropy production in a transonic compressor stage. Results for the adjoint optimization without geometry constraint and two comparative cases are detailed. It is indicated that three cases yield similar performance improvement;however, if geometry constraints are properly handled, the optimal designs have almost the same maximum thickness as the original design, compared to a thinner blade profile with 14% reduction of maximum thickness in the case without geometry constraint. The cases considering geometry constraints also consume slightly reduced Central Processing Unit(CPU) cost. Result of this work verifies the effectiveness of the proposed method to treat geometric constraints in adjoint optimization. | SU Xinrong MA Can YUAN Xin | 2019 | Journal of Thermal Science2019，28，5： | 3 |
| 2 | Dual stability enhancement mechanisms of axial-slot casing treatment in a high-speed mixed-flow compressor with various tip clearances显示文摘The influence of Axial-Slot Casing Treatment(ASCT)on the performance and stability enhancement mechanisms of ASCT were experimentally and numerically investigated in a highspeed mixed-flow compressor under three different tip clearances.Unsteady simulations showed the compressor stalled through end-wall stall route,i.e.the spike stall inception originating from rotor tip region,which was validated by dynamical measurements.When the ASCT was applied,greater than 20%of Stall Margin Improvement(SMI)could be achieved for the compressor under each tip clearance size.The streamwise velocity contours and flow structures in the tip region and axial slots were deeply analyzed to explore how the so called‘‘suction and injection effects'generated by the ASCT manipulate tip clearance flow and enhance the stability of compressor under different tip clearances.It was found that the dominant stability enhancement mechanisms of ASCT varies with tip clearance size for the mixed-flow compressor.(A)For the small tip clearance,the dominant mechanism of stability enhancement is the blockage reduction generated in the blade passage by the suction effect of ASCT.(B)For the large tip clearance,the injection effect of the ASCT is the dominant mechanism of stability enhancement with ASCT,which plays the leading role in delaying the spillage of incoming/tip leakage flow interface at the rotor Leading Edge(LE)plane. | Qianfeng ZHANG Juan DU Jichao LI Ming ZHAO Hongwu ZHANG | 2021 | Chinese Journal of Aeronautics2021，34，4： | 2 |
| 3 | Aeroelastic vibration analysis of a 1.5 stage compressor显示文摘Aeroelastic vibration problems are commonly found in modern compressors operating in off-design conditions.Large amplitude vibration could lead to high cycle fatigue(HCF)of blade and usually occurs in front stages of axial compressors.In this study,the influence of tip gap size on aeroelastic stability is analyzed in a 1.5 stage compressor with an in-house fluid-structure interaction code.A three-dimensional unstructured finite-volume compressible flow solver is applied in the fluid domain and a structure dynamic solver with the modal superimposition method for blade motion is used in the structure domain.Rotor tip clearances of 1%,2%and 3%of tip axial chord at maximum rotor loading conditions at off-design speeds are analyzed for aeroelastic stability.The tip leakage flow and vortex structure can be seen near the blade tip region at a larger tip gap size.The aeroelastic stability of rotor blade at different tip gap sizes is mainly influenced by the 1st torsion mode,and the variation of aerodynamic damping is not monotonous.The intensity of the tip vortex and shock wave are the key factors affecting the aeroelastic stability of rotor when tip gap size increases. | Yun Zheng Qingzhe Gao Hui Yang Kang Xu | 2020 | Propulsion and Power Research2020，9，1： | 1 |
| 4 | 基于差分探测的低相干外差干涉间隙测量技术显示文摘针对低相干外差干涉间隙测量技术应用于发动机、燃气轮机等设备内部高温、高压、强振等恶劣环境时,面临信号弱、信噪比差导致测量范围受限的问题,提出利用差分探测技术来提升拍频信号信噪比的方法。围绕所提出的方法,建立了严格的间隙测量模型,并从理论上说明了其具有提升信号信噪比、扩大测量范围的优势。为证明方法的可行性,搭建了全光纤低相干外差干涉间隙测量实验验证系统,进行单端探测与差分探测的间隙测量对比实验。实验结果表明在同等测量条件下,差分探测方式将信噪比提高了4.22倍,测量范围由10 mm增加到了20 mm。进一步,对系统的测量不确定进行了分析,理论和实验均表明,由于光纤延迟器件扫描速度的不稳定性,系统测量不确定度整体上具有随测量间隙增大而增大的趋势,但在20 mm测量范围内,测量不确定不超过15μm。 | 李靖 张伟 邵斌 樊星 章鹏 陈伟民 | 2021 | 光子学报2021，50，9： | 1 |
| 5 | 转子叶尖间隙形状对跨声速轴流压气机性能影响机理分析显示文摘为研究转子不同叶尖间隙形状对跨声速轴流压气机性能的影响机理,分别对平行式叶尖间隙进行渐变式和阶梯式改型优化,并利用商业软件NUMECA进行数值模拟。结果表明:对平行式叶尖间隙进行渐变式和阶梯式改型优化后,压气机性能有较大提高,改型后0.204-0.408的各类间隙压气机性能优于0.408-0.204间隙的。相比较平行间隙PTC 0.204-0.204,渐变式TTC0.204-0.408和阶梯式STC 0.204-0.408的失速裕度分别提高1.12%和1.61%,峰值效率基本不变,同时近失速工况下的总压比和效率也略有提高。叶尖泄漏涡得到抑制,间隙处的流体低速区明显减小,流动损失减小,流场得到较大改善。转子通道的总压比在85%叶高处明显提高,分别提高了1.01%和3.13%。阶梯式叶尖间隙压气机的静子通道40%叶高处总压损失系数减小达75.4%。对平行式叶尖间隙进行改型处理能够有效提高压气机性能,且阶梯式叶尖间隙比渐变式的对压气机性能提高的效果更加显著。 | 张成烽 张国臣 徐志晖 孙丹 刘鹏程 | 2023 | 航空发动机2023，49，3： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员