Computational Fluid Dynamics Simulation and Optimization of Hydropneumatic Spring Damper Valves for Heavy Vehicle Applications

Abstract

To satisfy the design requirements for a hydropneumatic spring damper valve, the inlet–outlet pressure drop (ΔP) and the axial force on the spool (FZ) of a valve were investigated using fluid–solid coupling simulations and multi-objective optimization, along with the effects of the diameters of three internal holes (DA, DB, and DC) in the valve on the ΔP and the FZ. First, a meshed computational fluid dynamics model of a damper valve was established based on its geometric structure. Next, the effects of the flow rate (Q) and the diameter of the damping hole in the internal structure on the ΔP and the FZ of the damper valve were investigated. The results showed that the ΔP and the FZ varied nonlinearly with Q. For a given Q, the ΔP decreased as DA, DB, and DC increased. For a given Q, the FZ was not related to DA and DC, but it decreased as DB increased. Finally, the structure of the damper valve was optimized by defining the ΔP and the FZ as the response variables and DA, DB, and DC as the explanatory variables. The results showed that the best configuration of the hole diameters was DA = 8.8 mm, DB = 5.55 mm, and DC = 6 mm. In this configuration, ΔP = 0.704 MPa and FZ = 110.005 N. The ΔP of the optimized valve was closer to the middle value of the target range than that of the initial valve design. The difference between the simulated and target values of the FZ decreased from 0.28% to 0.0045%, satisfying application requirements.

Modal Analysis of the Hydrodynamic Force of a Capsule in a Hydraulic Capsule Pipeline

“…To conclude, the motion of the capsule usually has one direction of freedom along the pipeline axis. However, hydrodynamic force represents excitation with complex spatial-temporal characteristics; so, the response of the system is also a complex process [34]. In this work, we propose a dynamic model to resolve the complex spatial-temporal process of capsule motion, thus enabling a modal analysis of hydrodynamic force instead of direct time-averaged results.…”