A conjugate heat transfer problem of a second-grade viscoelastic fluid past a stretching sheet has been studied. Governing equations include heat conduction equation of a stretching sheet, continuity equation, momentum equation, and energy equation of a second-grade fluid, analyzed by a combination of a series expansion method, the similarity transformation, and a second-order accurate finite-difference method. These solutions are used to iterate with the heat conduction equation of the stretching sheet to obtain distributions of the local convective heat transfer coefficient and the stretching sheet temperature. Ranges of dimensionless parameters, the Prandtl number Pr, the elastic number E and the conduction-convection coefficient N_(cc) are from 0.001 to 10,0.0001 to 0.01, and 0.5 to 2.0, respectively. A parameter G, which is used to represent the dominance of the buoyant effect, is present in governing equations. Results indicated that elastic effect in the flow could increase the local heat transfer coefficient and enhance the heat transfer of a stretching sheet. In addition, same as the results from Newtonian fluid flow and conduction analysis of a stretching sheet, a better heat transfer is obtained with a larger N_(cc), G, and E.
展开▼
机译:研究了通过拉伸片的二级粘弹性流体的共轭传热问题。控制方程包括拉伸片的热传导方程、连续性方程、动量方程和二级流体的能量方程,采用级数展开法、相似性变换法和二阶精确有限差分法相结合进行分析。利用这些解对拉伸片的热传导方程进行迭代,得到局部对流传热系数和拉伸片温度的分布。无量纲参数、普朗特数 Pr、弹性数 E 和传导对流系数 N_(cc) 的范围分别为 0.001 至 10、0.0001 至 0.01 和 0.5 至 2.0。参数 G 用于表示浮力效应的主导地位,存在于控制方程中。结果表明,流动中的弹性效应可以提高局部传热系数,增强拉伸片材的传热性能。此外,与拉伸板的牛顿流体流动和传导分析结果相同,较大的N_(cc)、G 和 E 可获得更好的传热。
展开▼