e.zakeri

In driving and when you brake, a lot of energy is dissipated to stop the car; especially in urban areas where the vehicle is driving in a stop-and-go pattern. This energy, which is dissipated by the brake pads, can be stored in the vehicle's battery. In Hybrid and Electric Vehicles, a regenerative brake can be used alongside the mechanical brakes to regenerate some energy while braking. The purpose of this article is to investigate the appropriate time to use the regenerative brake, the amount of energy recoverable versus the vehicle's speed, braking power and deceleration rate, the amount of energy on front and rear axles, to investigate the braking power to meet the two requirements of providing the required brake force and not locking the wheels (not to slide the wheels) and to investigate two parallel and fully controlled hybrid braking systems. To this end, a Dena hybrid vehicle was used and the recovered energy during Europe and Tehran city driving cycles was computed and compared with each other. The results shows a significant and efficient effect of the use of the regenerative brake system to utilize the braking energy and consequently the energy consumption reduction for the hybrid vehicles in Tehran city driving.

In this paper, Front Engine Accessory Drive (FEAD) system of automotive engine is modeled with ADAMS software. The model is validated using engine test data. It is then used to investigate the effect of design parameters on the system performance such as belt vibration and loads on the idlers. Three alternative layouts were developed in order to improve the performance of original EEAD system. The validated model was used to study the effect of changes made to the layouts on the reduction of vibration and loads. Several system outputs indicated that for the modified layouts, large reductions in vibration and loads were achieved. It was concluded that one of proposed layouts was more appropriate and could be a useful substitution to the original layout. The developed model also proved useful for the design of engine FEAD systems and could be used for further developments.