This article investigates the phenomenon of gravity-driven flow of nanoliquid film along a vertical surface under the effects of nonlinear thermal radiations. The falling nanofluid film is subjected to a convectively heated surface along with slip condition. The flow and thermal properties are investigated considering four different nanoparticles namely Ag (silver), Cu (copper), \(\mathrm {TiO}_2\) (Titania) and \(\mathrm {Al}_2\mathrm{O}_3\) (alumina) with water as a acting base fluid. The physical model is presented in terms of nonlinear partial differential equations. These equations are reduced to a system of nonlinear ordinary differential equations through similarity transformations. The problem is solved numerically utilizing Bvp4c function in MATLAB. Multiple solutions are presented for unfavorable buoyancy or opposing flow (\(\sigma <0\)) and favorable buoyancy or assisting flow (\(\sigma >0\)). The impact of nanoparticle volume fraction is found to be useful in intensifying the temperature and dropping heat transfer rate because of dominant convection. It is worth mentioning that silver nanoparticles in the thin film of nanofluid lead to higher wall shear stress and heat transfer rate. The increasing nature of skin friction coefficient \((C_f)\) is examined in buoyancy assisting flow while in opposing buoyancy flow its behavior is noticed reduced for various values of solid fraction (\(\phi \)) of \(\mathrm {Ag}\) nanoparticles.

本文研究了在非线性热辐射的作用下，纳米液体薄膜沿垂直表面重力驱动流动的现象。落下的纳米流体膜与滑移条件一起经受对流加热的表面。考虑四种不同的纳米粒子，即银（银），铜（铜），\（\ mathrm {TiO} _2 \）（二氧化钛）和\（\ mathrm {Al} _2 \ mathrm {O} _3 \）（氧化铝），以水为基础油。根据非线性偏微分方程表示物理模型。通过相似变换将这些方程简化为非线性常微分方程组。利用MATLAB中的Bvp4c函数以数字方式解决了该问题。对于不利的浮力或逆流（\（\ sigma <0 \））和有利的浮力或辅助流量（\（\ sigma> 0 \），提出了多种解决方案）。由于占优势的对流，发现纳米颗粒体积分数的影响可用于增强温度和降低传热速率。值得一提的是，纳米流体薄膜中的银纳米颗粒导致更高的壁切应力和热传递速率。皮肤摩擦系数的增大性质\（（C_F）\）检查在浮力辅助流，同时在相对的浮力流入其行为注意到了降低为固体分数的不同值（\（\披\） ）的\（\ mathrm { Ag} \）纳米粒子。