Title: Experimental and numerical insights on pipe flow stability mechanisms: a unified review

Authors: Saurabh Kapoor; Siprarani Sahoo

Addresses: Department of Education in Science and Mathematics, Regional Institute of Education, NCERT, Bhubaneswar, Odisha, India ' Department of Mathematics, Utkal University, Bhubaneswar, Odisha, India

Abstract: The present manuscript provides a unified review and comprehensive analysis of linear stability mechanisms in pipe flows, which are fundamental to understanding industrial applications namely, chemical reactors, nuclear cooling systems, and oil transport pipelines, along with natural processes including magma ascent, biological flows, and geothermal systems. The study synthesises key experimental and numerical investigations that validate and extend classical theoretical predictions. A broad range of numerical methodologies is reviewed, spanning traditional techniques such as the finite difference, finite element, and finite volume methods, alongside advanced approaches including spectral collocation methods, lattice Boltzmann methods, reduced-order modelling, and direct numerical simulation. Particular emphasis is placed on stability mechanisms in viscous and porous vertical pipe flows, highlighting the significant role of buoyancy-driven effects. The influence of governing parameters such as the Reynolds, Rayleigh, and Prandtl numbers on the onset of flow instabilities is systematically examined. By integrating theoretical, computational, and physical perspectives, this review offers a coherent framework for understanding convective instability in pipe flows and outlines key challenges and future research directions.

Keywords: pipe flow; stability analysis; experimental studies; numerical insights; unified review.

DOI: 10.1504/PCFD.2026.154641

Progress in Computational Fluid Dynamics, An International Journal, 2026 Vol.26 No.4, pp.263 - 275

Received: 09 Jul 2025
Accepted: 13 Oct 2025
Published online: 08 Jul 2026 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article