In the present work, the characteristics of physical model unsteady nanofluid flow and heat transfer in an asymmetric porous channel are analyzed numerically using wavelet collocation method. Using similarity transformation, unsteady two-dimensional flow model of nanofluid in a porous channel through expanding or contracting walls has been transformed into a system of nonlinear ordinary differential equations (ODEs). Then, the obtained nonlinear system of ODEs is solved via wavelet collocation method. The effect of various emerging parameters, such as nanoparticle volume fraction, Reynolds number (Re), and expansion ratio have been analyzed on velocity and temperature profiles. Numerical results have been presented in form of figures and tables. For some special cases, the obtained numerical results are compared with exact one and found that the results are good in agreement with exact solutions.

中文翻译：

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具有非对称可变矩形多孔通道的碳纳米管水基流体中流动和传热的小波策略

在目前的工作中，使用小波搭配方法对非对称多孔通道中物理模型非定常纳米流体流动和传热的特性进行了数值分析。使用相似变换，纳米流体在多孔通道中通过膨胀或收缩壁的非定常二维流动模型已转化为非线性常微分方程（ODE）系统。然后，通过小波搭配方法求解得到的常微分方程非线性系统。已经分析了各种新兴参数（例如纳米颗粒体积分数、雷诺数 (Re) 和膨胀比）对速度和温度曲线的影响。数值结果已以图形和表格的形式呈现。对于一些特殊情况，