Katarzyna Peta

Modelling of a contact pressure distribution caused by assembly errors in a spur gear transmission

Following paper presents development and results of finite element structural simulations prepared in order to estimate contact pressure distribution on teeth flanks of gear transmission caused by assembly errors. In first paragraphs, importance of alignment precision of gear transmission components is described. As well, influence of machining and assembly errors on spur gear transmission was introduced. In last part of introduction, innovations in spur gear transmissions assembly processes were described. Process of finite element analysis preparation was presented. Preparation of FEA included development of geometrical model, boundary conditions, discretization of model and definition of external loads. Results of conducted simulations was presented. Especially, contact pressure distribution irregularities caused by misalignment of shafts were examined Obtained data covered correlations between both direction and magnitude of assembly errors with contact stress distribution along tooth length. Conducted tests proved that in case of great-module geared transmission, shaft misalignments in plane which includes gears axes has far lesser influence on contact stress distribution than misalignments in perpendicular direction.

The influence of sodium chlorides fog on corrosion resistance of heat exchangers used in automotive

Abstract In the work, the most important factors which influence on the exploitative durability of heat exchangers are classified. Particular attention was paid to the compounds of sodium chloride used in the winter season for road maintenance. In order to determine their impact on automotive heat exchanger corrosion resistance, a test of heaters in a salt chamber which imitates the conditions of their work was realized. It also allows to verify the durability of these products. To evaluate the corrosion changes, observation with the use of light microscopy and scanning microscopy SEM were made supplemented with microanalysis of chemical composition by EDS spectroscopy method. Critical areas in the heat exchangers which are mostly exposed to damage including the formation of local corrosion pits were located and analyzed.

Diagnostic methods of detecting defects within the material with the use of active infrared thermovision

Abstract Article presents the methods of detecting defects within material with the use of active infrared thermovision. During the study ABS and PVC samples were used inside which internal structure defects and defects of glue conjunction between components were modeled. During combining composite materials with the use of glue joints, there is a problem with homogenous distribution of the glue layer on the surface of an element, which results in the creation of defects in joint structure and the decline of active surface of adhesion forces on the combined materials. It is then necessary to control the quality of the conjunction between the glued surfaces. The use of non-contact diagnostic methods allows to analyze a larger surface which conditions in more efficient quality control process. In the study, external heat excitation was used - optical excitation with periodic variable signal (LockIn method) and unit step excitation (Pulse method). The methods of analysis of the obtained thermograms are presented.