Applied Engineering Letters

80-86

Authors: T. Skrucany, M. Stopkova, O. Stopka, S. Milojević

The article focuses on detection of fuel consumption in cars with the sparkignition engine aiming to determine the most accurate way of daily-use fuel consumption through evaluation finding. To achieve relevant outcomes, different routes underwent experiments in multiple consumption modes. In particular, these encompass four circuits varying in length, speed limit, intersection number with significant waiting time and the route ratio city/highway. Each segment saw three measurings in terms of different consumption forms – standard, economical and dynamic. Apart from that, fuel consumption detection also takes into cosideration possible deviations from consumed fuel when automatically switching off the fuel pump pistol. Three methods contributed to achieving the findings; i.e. quantification method, the technique of data subtraction from the on-board computer (On-Board Unit) and method of amassing data from a phone application. Ultimately, compiled tables and detailed diagrams show outcomes demonstrating the most convenient way and approach of measuring fuel consumption for daily-users.

94-103

Authors: M. Gostimirovic, M. Sekulic, D. Rodic

This paper reports on the research results of surface integrity of the workpiece in creep-feed grinding on the high speed tool steel. The creepfeed grinding is an advanced abrasive process widely used in industry of complex and heavy engineering products. An experimental investigation of the fundamental characteristics of surface metallurgy and surface roughness is carried out. The metallurgical properties were determined by an optical microscope, and through: microstructure, microhardness, cracks and burns. The surface roughness was determined with multiple important roughness parameters through scanning the surface topography (roughness average, mean roughness depth, maximum roughness depth and profile bearing length ratio). The results show that the grinding surface integrity is acceptable with good material removal rate, so that the creep-feed grinding process is an excellent choice for efficient and quality material removal. However, creep-feed grinding is not suitable for the final machining because of the possible metallurgical alterations due to high thermal load.