Javaid Maria, Imran M, Imran M A, Khan I, Nisar K S
Department of Mathematics, Government College University, Faisalabad, Pakistan.
Department of Mathematics, University of Management and Technology Lahore, Lahore, 54770, Pakistan.
Sci Rep. 2020 May 20;10(1):8327. doi: 10.1038/s41598-020-64533-z.
In current study natural convection flow of second grade fluid in an oscillating infinite vertical cylinder is investigated. The dimensionless governing equations for temperature and velocity are obtained by introducing the non-dimensional variables. Exact solutions for temperature and velocity field are computed by means of integral transformation. Solutions for cosine and sine oscillations of velocity field are introduced in the form of transient and post-transient arrangements. A special case for Newtonian fluid is obtained from general results and transients solutions are computed in terms of tables. In the end, the impact of dimensionless numbers (Grashof and Prandtl numbers) at different values of time is presented in graphical form and found that velocity for Newtonian fluid has greater values than the second grade fluid. Furthermore, there are some comparisons of calculated solutions with existing solutions in literature.
在当前研究中,对振荡无限长垂直圆柱体内二级流体的自然对流流动进行了研究。通过引入无量纲变量,得到了温度和速度的无量纲控制方程。借助积分变换计算了温度和速度场的精确解。速度场的余弦和正弦振荡解以瞬态和后瞬态形式给出。从一般结果中得到了牛顿流体的特殊情况,并以表格形式计算了瞬态解。最后,以图形形式给出了不同时间值下无量纲数(格拉晓夫数和普朗特数)的影响,发现牛顿流体的速度值大于二级流体。此外,还将计算得到的解与文献中的现有解进行了一些比较。