侧翼扩散器分歧角度对风力轮机的影响:数值调查
Tahir Abbas Jauhar1, Muhammad Imtiaz Hussain2, Tayybah Kiren3
1Department of Mechanical Engineering, University of Gujrat, Gujrat, Pakistan.
PloS one
|June 15, 2023
概括
这项研究使用边缘扩散器增强了小型风力轮机的功率,实现了高达1.68倍的风速改善. 最佳设计将流量分离最小化,并最大限度地增加空气流量,以更好地捕获能量.
科学领域:
- 可再生能源工程可再生能源工程
- 空气动力学 航空动力学
- 流体动力学 流体动力学
背景情况:
- 小规模水平轴风力轮机 (HAWT) 的性能通常受到空气动力学因素的限制.
- 边形扩散器可以增加功率输出,但对扩散器角度和逆压等设计参数敏感.
研究的目的:
- 为了数值地研究风力轮机转子在边缘扩散器中的最佳位置.
- 分析不同扩散器角度和风速对功率增大和流量特征的影响.
主要方法:
- 计算流体动力学 (CFD) 用于建模和分析遮罩和边框配置.
- 实验验证在6m/s和8m/s进行,比较使用和不使用扩散器的性能.
主要成果:
- 4°的分歧角度消除了流量分离,最大限度地提高了流量,并实现了1.68倍的风速改进.
- 最佳的边缘高度被确定为250毫米.
- 最佳的风力轮机无维位置在0.45和0.5之间,分别为2°和4°的分歧角度.
结论:
- 带的扩散器设计显著提高了HAWT的性能.
- 优化扩散器角度和轮位置对于最大限度地提高功率至关重要.
- 这项研究为改善小规模风能系统提供了有价值的见解.
相关概念视频
Design Example: Calculating Safe Diameter for Wind-Exposed Disc
159
Assessing safety in wind-exposed installations is crucial to preventing potential failures. This example explores the calculation and design adjustments needed to mount a circular disc on a building facade, where wind forces are a primary concern. A 4-meter diameter disc was initially designed as an aesthetic feature facing winds at a velocity of 25 meters per second, with an air density of 1.25 kilograms per cubic meter. Given these conditions, the drag force on the disc was determined using...
159
Dimensional Analysis
346
Dimensional analysis is a valuable technique in fluid mechanics for simplifying complex problems by reducing them into dimensionless groups. These groups capture the essential relationships between the variables involved, allowing researchers and engineers to analyze fluid flow without dealing with each variable individually. This approach reduces the number of independent variables, allowing for easier analysis and better understanding of physical phenomena.
In fluid mechanics, dimensional...
In fluid mechanics, dimensional...
346
Divergence and Curl
1.8K
The divergence of a vector field at a point is the net outward flow of the flux out of a small volume through a closed surface enclosing the volume, as the volume tends to zero. More practically, divergence measures how much a vector field spreads out or diverges from a given point. For an outgoing flux, conventionally, the divergence is positive. The diverging point is often called the "source" of the field. Meanwhile, the negative divergence of a vector field at a point means that the...
1.8K
Wind Turbine Machine Models
171
In the growing field of wind energy, incorporating wind turbine models into transient stability analysis is essential. Induction and synchronous machines are the primary models used, with induction machines being prevalent due to their simplicity and reliability.
Induction machines interact through the rotating magnetic field generated by the stator and the rotor. The key parameter is slip, which is the difference between synchronous speed and rotor speed relative to synchronous speed. Slip is...
Induction machines interact through the rotating magnetic field generated by the stator and the rotor. The key parameter is slip, which is the difference between synchronous speed and rotor speed relative to synchronous speed. Slip is...
171
Design Example: Creating a Hydraulic Model of a Dam Spillway
233
Scaled hydraulic models of dam spillways provide a practical way to replicate and study the intricate flow dynamics of these structures. Often built to a 1:15 ratio, these models allow for observing critical water behavior, such as velocity distribution, flow patterns, and energy dissipation.
233
Conservation of Energy in Control Volume
876
Consider a turbine operating under steady-flow conditions. The control volume is drawn around the turbine, with fluid entering at one point and exiting at another. The turbine extracts energy from the fluid, which performs mechanical work (shaft work).
For steady flow systems, the time derivative of the stored energy becomes zero since there is no energy accumulation within the control volume. This simplifies the energy equation to:
For steady flow systems, the time derivative of the stored energy becomes zero since there is no energy accumulation within the control volume. This simplifies the energy equation to:
876


