## 6 Results and Discussion  
The present research has been carried out in order to study magnetohydrodynamics in the three-dimensional rotational flow of nanoparticles (single- and multi-walled carbon nanotubes) in the existence of non-linear thermal radiation along with heat generation or absorption based on the Casson fluid model over a stretching sheet. In this subsection we examine the physical outcomes of dissimilar embedded parameters with respect to the velocity distributions \(f^{\prime}(\eta),g(\eta)\) and temperature distribution \(\Theta(\eta).\) The influence of specific model quantities, such as \(K,M,Pr,Q_{h},\ Rd,\) and \(\lambda\) (the rotation parameter, magnetic parameter, Pandtl number, heat generation or absorption parameter, radiation parameter, and Biot number, respectively) on \(f^{\prime}(\eta),g(\eta),\) and \(\Theta(\eta)\) for SWCNTs and MWCNTs as nanoparticles is highlighted in the present discussion. Figure 1 shows the schematic flow geometry of the problem. Figures 2 and 3 present the convergence and probable choice of h-curve for \(f^{\prime\prime}(0),\ \Theta^{\prime}(0)\) and \(g^{\prime}(0).\) The effects of model values such as \(K,M,Pr,Q_{h},\ Rd,\)\(\lambda\) on \(f^{\prime}(\eta),g(\eta)\) and \(\Theta(\eta)\) are illustrated in Figures 4-14 and consequence are considered. Figure 4 demonstrates the consequence of rotation parameter \(K\) on the velocity profile \(f^{\prime}(\eta)\) for SWCNTs and MWCNTs. The increasing values of \(K\) depreciate the value of \(f^{\prime}(\eta)\) and result in a thinner boundary coating for SWCNTs and MWCNTs. Physically, when the value of rotation parameter \(K\) enlarges, the rate of rotation becomes dominant as compared to the stretching rate. Hence, there is a larger effect of rotation parameter \(K\) delivering resistance to the fluid stream. For the maximum value of the rotation parameter \(K\), the values of velocity-filled \(f^{\prime}(\eta)\) become small near the boundary, and the layer becomes thinner, so the x-coordinate of velocity component is a decreasing function of the rotation parameter \(K\). The similar impact for the high value of magnetic parameter \(M\) is shown in Figure 5 for both CNTs. It is obvious from the sketch that an increment in the magnetic parameter \(M\) depreciates the value of \(f^{\prime}(\eta)\). Usually, high values of magnetic parameter \(M\) improve the contradictory force (friction force), known as the Lorentz force. The corresponding force has the propensity to condense the value of \(f^{\prime}(\eta)\). The influence of volume fraction of nanoparticle \(\varphi\) on the velocity profile \(f^{\prime}(\eta)\) is exhibited in Figure 6 for SWCNTs and MWCNTs. We observe that increment in \(f^{\prime}(\eta)\) increases the quantity of \(\varphi\) for SWCNTs and MWCNTs. In fact, adding the nanoparticle \(\varphi\) enhances the energy and cohesive force between the atoms of the liquid, causing it to become frail and halt the faster liquid. Figure 7 illustrates the behavior of the Casson fluid parameter \(\beta\) on \(f^{\prime}(\eta)\) for SWCNTs and MWCNTs. With increasing values of the Casson fluid parameter \(\beta\) decreases the velocity field \(f^{\prime}(\eta)\) in the boundary layer. It is noted that to increases the value of the Casson fluid parameter \(\beta\) implies a reduction in the yield stress of the Casson liquid, and hence there is a clear acceleration in the motion of the boundary layer stream neighboring the stretching surface of the sheet. Moreover, it has been found that Casson fluids are similar to Newtonian fluids for large values of \(\beta\rightarrow\infty\). The impact of nanoparticle volume fraction \(\varphi\) on \(g(\eta)\) has been illustrated in Figure 8 for SWCNTs and MWCNTs. It is observed that the large value of \(\varphi\) decreases the transverse velocity \(g(\eta)\) for SWCNTs and MWCNTs. In Figure 9 the velocity distribution \(g(\eta)\) is intended for various values of rotation \(K\).