Homogeneous–Heterogeneous reactions on Darcy–Forchheimer flow of SWCNTs/MWCNTs over a bidirectional Riga plate with nonlinear radiation and non-uniform heat source/sink

The flow of carbon nanotubes (CNTs) via the Riga plate has a substantial influence, and it is used in the industrial sector, like fluid stirring, thermal reactors, semiconductors, tissue regeneration, gene delivery to organs, etc. However, the 3D Darcy–Forchheimer flow (DFF) of CNTs through the Riga plate with nonlinear thermal radiation and a non-uniform heat sink/source has not been investigated. As a consequence of this, the objective of this paper is to explore the impact of the nonlinear radiative DFF of water-based CNTs past a heated Riga plate with a non-uniform heat sink/source and homogeneous and heterogeneous reactions. In addition, the energy equation is constructed using the Cattaneo–Christov heat flux concept. By making use of appropriate variables, the governing flow models are mutated into a system of ordinary differential equations. These reduced equations are analytically and numerically computed by homotopy analysis method (HAM) and the bvp4c scheme. The brief discussion and visual depiction of the dominance of different factors on x- and y-direction velocities, thermal, nanoparticle concentration (NPC), surface drag coefficients, and local Nusselt number are presented in tables and figures. The growth of the Forchheimer number leads to a noticeable enrichment in the velocity profile in both directions. When the nanoparticle’s volume fraction and space-dependent heat source/sink parameters are increased, the thermal profile gets better. The NPC profile exhibits suppression as the intensity of both heterogeneous and homogeneous responses rises.