The present exploration deliberates the effect of nonlinear thermal radiation on double diffusive free convective boundary layer flow of a viscoelastic nanofluid over a stretching sheet. Fluid is assumed to be electrically conducting in the presence of applied magnetic field. In this model, the Brownian motion and thermophoresis are classified as the main mechanisms which are responsible for the enhancement of convection features of the nanofluid. Entire different concept of nonlinear thermal radiation is utilized in the heat transfer process. Appropriate similarity transformations reduce the nonlinear partial differential system to ordinary differential system which is then solved numerically by using the Runge–Kutta–Fehlberg method with the help of shooting technique. Validation of the current method is proved by having compared with the preexisting results with limiting solution. The effect of pertinent parameters on the velocity, temperature, solute concentration and nano particles concentration profiles are depicted graphically with some relevant discussion and tabulated result. It is found that the effect of nanoparticle volume fraction and nonlinear thermal radiation stabilizes the thermal boundary layer growth. Also it was found that as the Brownian motion parameter increases, the local Nusselt number decreases, while the local friction factor coefficient and local Sherwood number increase.

中文翻译：

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非线性热辐射对拉伸片上粘弹性纳米流体双扩散混合对流边界层流动的影响

本研究探讨了非线性热辐射对拉伸片上粘弹性纳米流体的双扩散自由对流边界层流动的影响。假定流体在存在磁场的情况下是导电的。在该模型中，布朗运动和热泳被分类为负责增强纳米流体对流特性的主要机制。在传热过程中采用了非线性热辐射的全部不同概念。适当的相似度转换将非线性偏微分系统简化为普通微分系统，然后借助Runge–Kutta–Fehlberg方法在射击技术的帮助下进行数值求解。通过将现有结果与有限解进行比较，证明了当前方法的有效性。以图形方式描绘了相关参数对速度，温度，溶质浓度和纳米颗粒浓度分布的影响，并进行了一些相关的讨论和列表结果。发现纳米颗粒体积分数和非线性热辐射的作用稳定了热边界层的生长。还发现，随着布朗运动参数的增加，局部的努塞尔特数减少，而局部的摩擦系数和局部的舍伍德数增加。以图形方式描绘了溶质浓度和纳米颗粒浓度分布图，并进行了一些相关讨论并列出了结果。发现纳米颗粒体积分数和非线性热辐射的作用稳定了热边界层的生长。还发现，随着布朗运动参数的增加，局部的努塞尔特数减少，而局部的摩擦系数和局部的舍伍德数增加。以图形方式描绘了溶质浓度和纳米颗粒浓度分布图，并进行了一些相关讨论并列出了结果。发现纳米颗粒体积分数和非线性热辐射的作用稳定了热边界层的生长。还发现，随着布朗运动参数的增加，局部的努塞尔特数减少，而局部的摩擦系数和局部的舍伍德数增加。