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Prediction and analysis of the thermo-mechanical coupling behavior in friction braking system is very important for the design and application of vehicle brakes, such as brake judder, brake squeal, brake wear, brake cracks, brake fade. This paper aims to establish a macro-structural model of the thermo-mechanical dynamics of the ventilated disc brake with asymmetrical outer and inner disc thickness, taking into account the friction-velocity curve of the disc pad couple acquired by testing. On the basis of finite elements analysis of the model, the predictions of the thermo-mechanical responses of the brake disc are presented, including disc transient temperature field and normal stress in radial, circular and axial directions, disc lateral deformation and disc thickness variation. Numerical predictions of the disc surface temperature and later distortion are compared with experimental measurements obtained by thermocouples and non-contact displacement sensors.

An adaptive sideslip angle observer based on discrete extended Kalman filter (DEKF) is proposed in this paper and tire-road friction adaptation is also considered. The single track vehicle model with nonlinear tire characteristics is adopted. The tire parameters can be easily obtained through road test data without using special test rig. Afterwards, this model is discretized and the maximum value of tire-road friction is modeled as the third state variable. Through the measurement of vehicle lateral acceleration and yaw rate, the tire-road adhesion coefficient can be timely updated. Simulations with experimental data from road test and driving simulator have confirmed that DEKF has very high accuracy. The convergent speed of DEKF relies on the magnitude of lateral excitation.

Effects of biodiesel fuel on nucleation mode particles were studied on a direct injection, high pressure common-rail diesel engine for passenger cars. Particle number and size distribution of the diesel engine were obtained using an Engine Exhaust Particle Sizer (EEPS). The base petroleum diesel, three different blend ratios of petroleum diesel/biodiesel (10%, 20% and 50% v/v biodiesel blend ratios), and the pure biodiesel fuel (obtained and converted from Jatropha seed in China) (B0, B10, B20, B50 and B100 fuels) were tested without engine modification. Experiments were performed on a series of engine operating conditions. The particle number size distribution of the engine shows unimodal or bimodal log-normal distribution. With the biodiesel blend ratios increasing, the number of nucleation mode particles increases at all test engine operating conditions and accumulation mode particles decreases at most engine operating conditions.