在具有零压差梯度的同热加热平板上对流边界层进行多尺度分析
Md Shahneoug Shuvo1, Md Jisan Mahmud1, Sumon Saha1
1Department of Mechanical Engineering, Bangladesh University of Engineering and Technology, Dhaka, 1000, Bangladesh.
Heliyon
|December 13, 2023
概括
斯帕拉特-阿尔马拉斯模型准确地预测了边界层中的流热传递. 一个多尺度分析揭示了一个独特的对数中间层影响流量和热特性.
科学领域:
- 流体动力学 流体动力学
- 热传递热量转移的方法
- 流建模 流建模
背景情况:
- 流边界层在许多工程应用中至关重要,但准确预测热传递仍然具有挑战性.
- 现有的流模型对于热边界层预测的有效性各不相同.
研究的目的:
- 为了比较八个流模型的性能,以预测流边界层中的热传递.
- 研究不同条件下的热和流场的多尺度特征.
主要方法:
- 使用雷诺兹-平均纳维埃-斯托克斯方程和热能方程,对流边界层进行数值模拟.
- 对八种流模型的比较分析:代数 yPlus,标准 k-ω,标准 k-ε,长度-速度,Spalart-Allmaras,低雷诺兹数 k-ε,切削应力传输和v2-f.
- 采用四层结构方案的多尺度调查,使用不同的雷诺斯和普兰特尔数.
主要成果:
- 斯帕拉特-阿尔马拉斯模型与流热传递的直接数值模拟数据显示出了很好的一致性.
- 控制非维数对平均热量和流量特征有重大影响.
- 在平均热和动量场的缩放中,确定了一个独特的对数介质层.
- 雷诺兹数缩放最好地描述了流场的多缩放分析.
结论:
- 斯帕拉特-阿尔马拉斯模型是预测流热传递的可靠工具,特别是在更高的普兰特尔和雷诺兹数下.
- 在流边界层内存在一个独特的中间层,影响热量和动量传递.
- 虽然内层和中间层的缩放是一致的,但外层的缩放显示与四层理论的小差异.
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