Determination of Static Flow Characteristics of A Prototypical Differential Valve Using Computational Fluid Dynamics

The paper describes the numerical calculations of a conceptual air brake valve of a trailer equipped with a differential section, which is intended to shorten response time and braking distance. The static flow characteristics have been determined using computational fluid dynamics (CFD). Mixed (global and local) computational meshes were used in the paper to determine the static flow characteristics of the valve sections. The use of the local mesh was relevant for valve openings smaller than 0.5mm. Using CFD, it was possible to determine the static flow characteristics of the main, auxiliary feed and the differential sections, which were linear, degressive and progressive depending on the section. The analyzes, which have not yet been described in the literature, showed a significant difference in the MFR of the additional and main feed tracts, which reached 52.29%.The results are applicable to the configuration of the braking system. Further research will include performing dynamic simulations using dedicated software and building a test rig to validate the CFD calculation results.