An optimization procedure of shape and position of the aerodynamic device at the rear side of a semi-trailer truck model.

The paper outlines the development and optimization of an aerodynamic device for a semi-trailer truck model to reduce aerodynamic drag force. The optimization procedure involves the selection of a basic aerodynamic device shape, using airfoil profiles, and refining its shape and position through established optimization techniques like Full Factorial Design and Response Surface Method within the Design of Experiments framework. The test subject is a 1:10 scale model of the semi-trailer truck.

The emission of BTEX compounds during movement of passenger car in accordance with the NEDC.

The results of the research in the field of benzene, toluene, ethylbenzene and xylene isomers (BTEX) concentrations in exhaust gases of spark ignition engines under different operating conditions are presented in this paper. The aim of this paper is to gain a clearer insight into the impact of different engine working parameters on the concentrations of BTEX. The experimental investigation has been performed on the SCHENCK 230 W test stand with the controlled IC engine.