الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 95 |  |  |
| | | from | 95 | | |
Abstract
Although performance of road vehicles has been in use for many years, little effort has been made to model these systems. The overall system configuration has remained merely unchanged, only minor system modifications have been made in order to meet the demands of today’s customers. Most of the research has been conducted on modeling components or on simple characteristics of the half car suspension system. A few researches develop aerodynamic, dynamic and fluid structure interaction of half car 4 DOF, “Skoda Octavia A4” model is used for the simulations regarding the performance and studding the characteristics of the vehicle. In the present work, the main task is to introduce in detail a half car suspension model to study the vehicle performance during a moving over smooth road and bump situation. The vehicle model is simulated with the help of software COMSOL. The simulation results were classified into three parts, the first is studding the Fluid structure interaction simulation with and without road profile which is selected according to a live road simulation for different cruise speeds. The second part is studding the Computational fluid dynamics simulation also with and without road profile for the same cruise speeds selected; this model allows us to follow the results of the aerodynamic forces. Finally, the third part of simulation is the results of the dynamic model of the vehicle and variations of parameters resulted from simulation as forces, displacement, pitching moment, pitching angle, transverse velocity and accelerations of the vehicle C.G. for the same road types and cruise speeds used before. The vehicle dynamics included in FSI causes a decrease in the value of drag force due to the damping enforced; on the other hand, the dynamics has a slight effect on the lift force. The aerodynamic forces included in the FSI simulation has a major effect on the displacement, pitching angle, transverse velocity and transverse acceleration. It is recommended for simulations at low cruise speeds below 36 km/hr, where the deformation of mesh does not occur (no interaction), to use the dynamic model simulation which can save time and effort, however for the other cruise speeds we have to take into consideration the effect of aerodynamic forces with the presence of FSI model.