Mobility and Vehicle Mechanics

1-9

Authors: Nadica Stojanović, Jasna Glišović, Jovanka Lukić, Ivan Grujić

Brake is a device for slowing or stopping the vehicle. The sound that occurs in the process of braking is very irritating for the driver. Brake systems of road vehicles as important factor in overall vehicle noise have attracted great attention. All global brake system manufactures are focused to the quieter brakes. This paper presents an analysis of differentially variants of brake disc, and how the structure itself influencing the occurrence of noise. The weight of analyzed discs is approximately equal to each other. The analysis was performed in the software package ANSYS, while the model was created in CATIA.

31-48

Authors: Dušan Gruden

Regulations of the European Union are demanding that re-use of materials should be taken into account already in the design phase of new vehicles and to provide instructions about exploitation of the old cars. When engineering a car, every part of the vehicle is analysed in terms of ecological criteria: "the possibility of re-use of materials", "convenience for recycling" and "critical materials". The primary principle of "Design for recycling" is using a closed circuit of materials. Recycled material must fully correspond to the new material in all its properties. Analysis of different materials shows that with the increasing application of recycled materials substantial savings in energy consumption and raw materials can be achieved. Selection of plastic materials plays a very important role in the engineering of the car taking into account the recycling. Labelling the plastic allows its clean sorting and re-use. In addition, an important criterion is easy disassembly of the parts to be used again. Car producers are obliged to prepare manuals for disassembling for each vehicle.

63-71

Authors: Gordana Bogdanović, Dragan Milosavljević, Aleksandar Radaković, Dragan Čukanović, Vladimir Geroski

Mechanical behaviour of anisotropic media may be seen the best through its behaviour during bulk wave propagation. Such waves may be decomposed into finite plane waves propagating along arbitrary direction n in solid. Properties of these waves are determined by dependence between propagation direction and constitutive properties of media. Three types of such waves may be distinguished in connection to three displacement vectors, which determine acoustic polarization. The most of dynamical systems are naturally nonlinear; here we are going to write Reimann-Christoffel equation. This equation represents propagation condition of bulk waves as set of three homogeneous linear equations. Materials used in present analysis are fibre reinforced with one or two families of continuous fibres. Often used represent of such materials is epoxy resin carbon fibres composite whose material constants are determined with ultrasound methods.