AIRCRAFT HYDRAULIC DRIVE ENERGY LOSSES AND OPERATION DELAY ASSOCIATED WITH THE PIPELINE AND FITTING CONNECTIONS

Theoretical research on hydraulic processes occurring in aircraft hydraulic drives is presented in the studies. Installation of angular fitting connections in aircraft pipeline systems influences hydrodynamic processes and fluid flow characteristics analysed in the research. The provided analysis is based on a validated numerical model utilizing Navier–Stokes equations and the k-epsilon turbulence model. Fluid flow inside the aircraft hydraulic drive pipeline system was investigated with flow rates up to 100 l/min. A mesh independence study was conducted for numerical simulation of the fluid flow. The obtained results include fluid pressure drops, energy losses, and operational delays associated with fluid flow vortex formations at 45° and 90° angular fitting connections. Additionally, compared results from standard methods of calculation for angular fitting connections, including the equivalent length and equivalent length same shape methods.