数字研究对不均的尖端空隙对旋转器尖端空隙流场结构的影响
Guochen Zhang1, Zhipeng Li1, Zhiyuan Cao2
1School of Aero-Engine, Shenyang Aerospace University, Shenyang, China.
Heliyon
|February 9, 2024
概括
将轴压缩机尖端空隙修改为正弦型 (STC) 和型 (HTC) 显著提高了峰值效率和阶段负载 (SMI). 这些设计减少了泄漏和的强度,与传统的平行空隙相比,提高了压缩机的整体性能.
科学领域:
- 航空航天工程 航空航天工程
- 流体动力学 流体动力学
- 轮机的机械设备
背景情况:
- 轴压缩机在航空航天推进和发电方面至关重要.
- 尖端空隙流量显著影响压缩机的效率和稳定性.
- 传统的平行小费清算可以导致性能损失.
研究的目的:
- 为了研究非均的尖端空隙形状对NASA Stage 35轴向压缩机性能的影响.
- 分析性能改进背后的空气动力学机制,使用正弦型 (STC),型 (HTC) 和型 (CTC) 尖端空隙.
- 了解尖端泄漏流量,旋结构和压缩机停机之间的关系.
主要方法:
- 美国宇航局35阶段轴向压缩机的数值模拟.
- 实施三个不同的非统一的尖端空隙几何结构:STC,HTC和CTC.
- 分析流场特征,包括尖端泄漏流量,旋动力学和冲击结构.
主要成果:
- 与基线相比,STC和HTC显著提高了峰值效率和阶段负载 (SMI) 分别为3.102%和2.672%.
- 不统一的尖端空隙减少了尖端泄漏流量和尖端泄漏 (TLV) 的强度.
- STC和HTC导致降低低速度,高和高旋转区域,改善冲击动力学和增加刀片负荷.
- 与基线相比,CTC显示性能恶化,表明形状灵敏度.
结论:
- 不统一的尖端空隙,特别是STC和HTC,为提高轴向压缩机性能提供了一个可行的策略.
- 通过优化尖端形状来减少尖端泄漏和TLV强度是提高效率和停机率的关键.
- 该研究强调了尖端空隙几何,泄漏流量和压缩机内部空气动力学之间的复杂相互作用.
相关概念视频
01:16Bernoulli's Equation for Flow Normal to a Streamline
861
Bernoulli's equation for flow normal to a streamline explains how pressure varies across curved streamlines due to the outward centrifugal forces induced by the fluid's curvature. The pressure is higher on the inner side of the curve, near the center of curvature, and decreases outward to balance these centrifugal forces.
The pressure difference depends on the fluid's velocity and radius of curvature. The pressure variation is minimal in flows with nearly straight streamlines.
The pressure difference depends on the fluid's velocity and radius of curvature. The pressure variation is minimal in flows with nearly straight streamlines.
861
01:26General External Flow Characteristics
162
The study of external flow is essential for creating structures and objects that interact efficiently and safely with moving fluids, such as air or water. When a body is immersed in a flowing fluid, it experiences two primary forces: drag, which opposes motion along the flow direction, and lift, which acts perpendicular to the flow. The shape, size, and orientation of the object influence these forces.Streamlined and Blunt Bodies in External FlowObjects in fluid flow are classified as...
162
01:23Steady, Laminar Flow in Circular Tubes
209
Hagen-Poiseuille flow describes a viscous fluid's steady, incompressible flow through a cylindrical tube with a constant radius R. This flow profile is often applied to understand fluid transport in narrow channels, such as capillaries. It serves as a foundational example of laminar flow. In this model, cylindrical coordinates (r,θ,z) are used to describe the radial (r), angular (θ), and axial (z) dimensions within the tube. For Hagen-Poiseuille flow, the velocity profile is...
209
01:17Steady, Laminar Flow Between Parallel Plates
194
Understanding steady, laminar flow between parallel plates is essential for analyzing and designing flow in narrow rectangular channels, commonly found in various water conveyance and drainage systems. The Navier-Stokes equations govern fluid motion and are generally challenging to solve due to their nonlinearity. However, simplifications are possible in certain cases, like the steady laminar flow between parallel plates. For this scenario, we assume steady, incompressible, laminar flow.
194
01:30Bernoulli's Equation for Flow Along a Streamline
969
Bernoulli's equation relates the energy conservation in a fluid moving along a streamline. The equation applies to incompressible and inviscid fluids under steady flow. For such a flow, Newton's second law is applied to a small fluid element, which experiences forces due to pressure differences, gravity, and velocity variations. The force balance leads to the following form of Bernoulli's equation:
969
01:30Typical Model Studies
359
Fluid mechanics model studies often utilize scaled-down systems to predict fluid behavior in full-scale environments, such as river flows, dam spillways, and structures interacting with open surfaces. Maintaining Froude number similarity in river models is crucial, as it replicates surface flow features like wave patterns and velocities.
359