• DEVELOPMENT OF A CAR BODY DESIGNING PROCESS

    Machines. Technologies. Materials., Vol. 9 (2015), Issue 7, pg(s) 9-12

    Car industry is one of the first industries that started using computers in the designing process. A replacement of a conventional designing process has been a long-lasting procedure, especially regarding collaboration. In addition to the necessity for designers’ training and changes in the way of thinking, considerable investments were needed as well. The ambitious goals were not accomplished after all, since the entire process had been conditioned by a large number of participants at various development levels. In this paper, the differences between the conventional designing, designing by computers and virtual designing are presented. A new model was produced, without manufacture of classic prototypes which were replaced by vehicles from the test production. There are the upcoming analyses of the effects, which will certainly influence further development of the designing process.

  • DEVELOPMENT OF A CAR BODY DESIGNING PROCESS

    Machines. Technologies. Materials., Vol. 9 (2015), Issue 6, pg(s) 43-46

    Car industry is one of the first industries that started using computers in the designing process. A replacement of a conventional designing process has been a long-lasting procedure, especially regarding collaboration. In addition to the necessity for designers’ training and changes in the way of thinking, considerable investments were needed as well. The ambitious goals were not accomplished after all, since the entire process had been conditioned by a large number of participants at various development levels. In this paper, the differences between the conventional designing, designing by computers and virtual designing are presented. A new model was produced, without manufacture of classic prototypes which were replaced by vehicles from the test production. There are the upcoming analyses of the effects, which will certainly influence further development of the designing process.

  • THE EFFECT OF FUEL VARIATION ON FLAME PROPAGATION IN IC ENGINES WITH STRONG MACRO FLOWS

    Machines. Technologies. Materials., Vol. 8 (2014), Issue 6, pg(s) 20-23

    In this paper some results concerning the evolution of flame propagation through unburnt mixture of two different hydrocarbon fuels,such as CH4 and C8H18, in engines with strong macro flows were presented. Flame propagation was represented by the evolution of spatial distribution of temperature in various cutplanes within combustion chamber. Flame front location was determined in zones with maximum temperature gradient. All results were obtained by dint of multidimensional modeling of reactive flows in arbitrary geometry of IC engine combustion chamber with moving boundaries. In 4.-valve engines the fluid flow pattern during intake is characterized with organized tumble motion pursued by small but clearly legible deterioration in the vicinity of BDC. During compression the fluid flow pattern is entirely three-dimensional and fully controlled by vortex motion located in the central part of the chamber. For that reason these engines are designated as IC engines with strong macro flows (swirl, squish, tumble) yielding non-spherical flame shapes usually encountered in quiescent flows. Flame propagation results for both fuels were obtained with eddy-viscosity model i.e. with standard k-ε model of turbulence.
    The interplay between fluid flow pattern and flame propagation is entirely invariant as regards fuel variationindicating that flame propagation through unburnet mixture of CH4 and C8H18 hydrocarbon fuels is not chemically controlled but controlled by dint of turbulent diffusion.

  • COMPARISON OF THE EFFECTS OF INDIVIDUAL AND PRODUCTION ADJUSTMENT OF VEHICLES FOR LPG APPLICATION

    Machines. Technologies. Materials., Vol. 8 (2014), Issue 2, pg(s) 15-18

    The paper presents the results of developmental researches related to determining the influence of application of various systems for LPG on vehicle properties. On model Florida Zastava the following sequential systems were installed: Sequent 24 BRC, Omegas LR, e-G@S, Fast Lovato and Alisei N Zavoli. The results of comparative investigations obtained indicate the advantages of particular systems. The results of individual adjustment have been compared with the results of a production vehicle adjustment.