A Detailed Model for Simulation of Hydrodynamic Processes in Hydraulic Braking System with ABS on Motor Vehicles

Abstract

Aims: Vehicle braking system represents the most important active security system of modern vehicles. For proper functioning of additional equipment on systems such as ABS, TCS, ESP etc, it is necessary to know the changes in pressure in the entire braking installation. Study Design: The work presents a model for calculating parameters in a braking installation with hydraulic signal transfer. Simulation of hydrodynamic parameters in the brake installation with ABS covered a realistic compressible fluid (braking fluid) and the transfer of signal through the fluid in a form of wave motion. Place and Duration of Study: Faculty of Mechanical Engineering University of Sarajevo, Department for IC Engines and Vehicles leads the researching, while beta runway of International Airport Mostar was used for the measurements. Duration of study: 6 months during 2014 and 2015. Methodology: The method of characteristics is used for calculating hydrodynamic parameters in the pipes of braking installation, and for solving the mass conservation equations, where the compressibility of a fluid is present, the Runge-Kutta forth order method with a variable time step is used. This way it is enabled to define a response of a system for every wheel separately, having in account that the pipes of the braking installation are of different lengths. Results: Numerical results are experimentally proofed, which affirms the use of this method of determining hydraulic parameters in the braking installation and it allows an analysis of realistic conditions of braking of a vehicle under all environmental conditions. Conclusion: A good model for simulation of complete vehicle hydraulic brake system.