Exact solutions for the magnetised flow of fractional NTNN fluid subject to an oscillating rectangular duct
摘要
This paper explores the complex dynamics of time-dependent, two-dimensional flow of an incompressible fractional Nadeem trigonometric non-Newtonian (NTNN) fluid experiencing cosine oscillations in a rectangular duct caused by an external magnetic field. The primary goal is to find practical analytical solutions for the fluid flow described by a time-fractional derivative-based initial-boundary value problem. A method employing both Laplace and double Fourier sine transforms is used to simplify the governing equations. A detailed parametric analysis is performed to examine how the fractional order α, rheological parameter N, oscillation frequency ω, time t and magnetic field strength M affect the velocity profile and shear stress of the fluid. The results indicate that increasing values of α, N, ω and t lead to higher fluid flow, while stronger magnetic fields produce a damping effect. In certain limiting cases, the model reduces to the conventional NTNN and classical Newtonian fluid flows, thereby confirming the versatility and robustness of the analytical solution.