Electro-osmotic peristaltic propulsion of a PTT fluid with ciliary motion in rough-walled channels with thermal radiation: Micro-fluidic and biomedical applications

Electroosmotic transport and metachronal ciliary motion play a pivotal role in enhancing the pumping efficiency and transport characteristics physiological pumping mechanism and bio-microfluidic systems. Motivated by their significant biomedical and engineering applications, the main target of this paper is to analyze the role of metachronal ciliary motion and electro osmosis effects on the bioconvective peristaltic transport of Phan-Thien-Tanner (PTT) viscoelastic biofluid in a two-dimensional rough walled channel. Also, the consequences of heat transfer and thermal radiation are taken into the consideration. In addition, the inclusion of wall roughness provides a more realistic representation of biological conduits, such as microcirculatory vessels and mucus-lined respiratory passages, thereby enhancing the physiological relevance and practical applicability of the applied model. The governing equations are simplified using the lubrication approximation and the Debye-Hückel linearization. Exact analytical solutions of the resulting boundary value problem are obtained and implemented in Mathematica to examine the influence of the relevant physical parameters. According to the observation, it is identified that the PTT fluid velocity declines with the climb in the Helmholtz-Smoluchowski parameter ( U H s ) , Electro-osmotic parameter ( m ) , Weissenberg number W e , Cilia length ( β ) , while it enhances with surface roughness parameter ϕ 0 . The PTT fluid temperature profile strengthens when the Brinkman number B r increases. As the electro-osmotic parameter m increases, the streamlines become straighter, indicating electro-osmotic slip-dominated flow, while higher U H s intensifies flow distortion caused by surface roughness and channel non-uniformity. The study highlights the importance of coupling electro-osmosis, viscoelasticity, and thermal radiation for accurate prediction of biomedical and thermal engineering transport phenomena.