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A simple finite element model for the pads, caliper and mounting of a car disc brake system is built and its dynamic influence to the disc is established. The disc is modeled as a thin plate in sliding contact with the pads. Through the contact conditions, the dynamics of the whole disc brake system is formulated. The friction-induced instability of the disc brake system is analyzed for different system parameters and operating conditions so that their influences on the dynamic instability and squeal are understood. Numerical simulation indicates that in the specific cases considered reasonably stiff pads tend to reduce the likelihood of squeal.

The investigation and results presented hereafter are based on the use of a novel technique to improve the performance and emission characteristics of gasoline and diesel engines. The technique involved generating corona discharges within the engine's pre-combustion air stream. These discharges were created by a multi-points charged electrodes. The onset of the discharges facilitated the ionization and excitation process of the neutral air species. New radicals and highly oxidizing species such as atomic oxygen (O) and ozone (O3) were produced and these are known to modify some of the chemical reactions involved in the combustion of hydrocarbon fuels. Measurements of both gasoline and diesel engine torque, speed, various temperatures, fuel consumption and exhaust gas composition were obtained, using a constant throttle position under both normal and coronas operating conditions.