• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>International Journal of Heat and Mass Transfer >Two-dimensional unsteady forced convection heat transfer in power-law fluids from a cylinder
【24h】

Two-dimensional unsteady forced convection heat transfer in power-law fluids from a cylinder

机译：汽缸中的幂律流体中的二维非稳态强迫对流换热

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Forced convection heat transfer characteristics of a cylinder (maintained at a constant temperature) immersed in a streaming power-law fluids have been studied numerically in the two-dimensional (2-D), unsteady flow regime. The governing equations, namely, continuity, momentum and thermal energy, have been solved using a finite volume method based solver (FLUENT 6.3) over wide ranges of conditions (power law index, 0.4≤n≤1.8; Reynolds number, 40≤Re ≤140; Prandtl number, 1≤Pr≤100). In particular, extensive numerical results elucidating the influence of Reynolds number, Prandtl number and power-law index on the isotherm patterns, local and average Nusselt numbers and their evolution with time are discussed in detail. Over the ranges of conditions considered herein, the nature of flow is fully periodic in time. The heat transfer characteristics are seen to be influenced in an intricate manner by the value of the Reynolds number (Re), Prandtl number (Pr) and the power-law index (n). Depending upon the value of the power-law index (n), though the flow transits from being steady to unsteady somewhere in the range ～33 < Re < 50, the fully periodic behavior is seen only beyond the critical value of the Reynolds number (Re). As expected, the average Nusselt number increases with an increase in the values of Reynolds and/or Prandtl numbers, irrespective of the value of the flow behavior index. A strong influence of the power-law index on both local and time-averaged Nusselt numbers was observed. Broadly, all else being equal, shear-thinning behavior (n < 1) promotes heat transfer whereas shear-thickening behavior (n > 1) impedes it. Furthermore, this effect is much more pronounced in shear-thinning fluids than that in shear-thickening fluids.
机译：研究了二维（2-D）非定常流动状态下浸没在流动幂律流体中的气缸（保持在恒定温度下）的强制对流传热特性。控制方程，即连续性，动量和热能，已使用基于有限体积方法的求解器（FLUENT 6.3）在宽范围的条件（幂律指数，0.4≤n≤1.8；雷诺数，40≤Re≤）下求解。 140；普朗特数，1≤Pr≤100）。特别是，详细讨论了广泛的数值结果，阐明了雷诺数，普朗特数和幂律指数对等温线图，局部和平均努塞尔数及其随时间演变的影响。在本文考虑的条件范围内，流动的性质在时间上是完全周期性的。可以看出，传热特性受到雷诺数（Re），普朗特数（Pr）和幂律指数（n）值的复杂影响。取决于幂律指数（n）的值，尽管在〜33 1）阻碍了传热。此外，这种作用在稀浆化流体中比在稀浆化流体中更为明显。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号