A comparative study on flow-induced phenomena of servo-valve for realizable k-ξ and spalart-allmaras turbulence model under malfunction

Abstract

Servo-valves are widely used in the aerospace, mechanical, and aeronautics sectors, where precise control of missile fins and aircraft components is essential. This study presents a details comparison between the Realizable k-ε turbulence model and the Spalart-Allmaras turbulence model to evaluate flow behavior and its impact on servo-valve malfunction. This article highlights the critical role of electrohydraulic servo-valves in ensuring the performance and reliability of the servo control systems. Computational fluid dynamics (CFD) is employed to analyze pressure distribution, velocity patterns, and flow behaviors within the pilot stage of the servo-valves. Additionally, mesh refinement techniques are applied to achieve optimal accuracy and computational efficiency in capturing flow physics. Significant variations in pressure and velocity fields are observed, demonstrating the differing predictive capabilities of the turbulence models in capturing flow-induced effects. Therefore, this study provides valuable insights for improving servo-valve design and mitigating performance degradation caused by flow-related malfunctions.

J. Bangladesh Acad. Sci. 50(1); 23-34: March 2026