在增材制造的迷你通道上应用的层状热传递上的粗度效应的CFD
Mohammadreza Kadivar1,2, David Tormey1,2, Gerard McGranaghan1,2
1Centre for Precision Engineering Material and Manufacturing Research (PEM Centre), Atlantic Technological University, Sligo, F91 YW50 Ireland.
概括
增材制造的迷你通道的表面粗度显著影响热传递和流量. 较高的粗度增强了热传递和摩擦,特别是在较高的雷诺兹数下,这是由于粗表面内的复杂流动相互作用造成的.
科学领域:
- 热力工程是热力工程中的一个.
- 流体动力学 流体动力学
- 添加剂制造 添加剂制造 添加剂制造
背景情况:
- 增材制造使热传递应用中复杂的几何结构成为可能.
- 增材制造道的表面粗性可能会对热性能产生负面影响.
研究的目的:
- 在粗的迷你通道中研究层状强迫对流的热流体特性.
- 量化表面粗度对传热和流电阻的影响.
主要方法:
- 开发了3D高斯粗度的数值模型.
- 采用有限体积法来解决正方形迷你通道中的联合热传递.
- 对200至1600的雷诺兹数进行模拟的层流.
主要成果:
- 增加雷诺兹数可以增强热传递和流电阻.
- 0.0068,0.0113和0.0167的相对粗度使摩擦因子增加了1.56-2.91%.
- 随着粗度和雷诺兹数的增加,努塞尔特数增强至46.05%
结论:
- 表面粗性显著影响微通道中的热传递和流动摩擦.
- 粗度谷可以减少热传递,而峰值和循环再循环可以增强热传递.
- 较高的粗性通常会导致更好的热性能和更高的流电阻.
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