The stress-life approach is standardized and widely accepted for determining fatigue damage. It was extended to non-isothermal cases by introducing an equivalent temperature approach (ETA). The paper presents its extension, the damage operator approach (DOA), enabling continuous damage calculation for isothermal and non-isothermal loading with mean stress correction. The cycle closure point, equivalent temperature, threshold temperature and rainflow counting are not necessary for the DOA any more. Both approaches are equivalent for the second run of block loading if temperature is constant.
COBISS.SI-ID: 10955291
The test rig and the possibilities of adjustments are presented. In order to carry out a dynamic analysis of the drive and determine the load ontest rig elements, computer program has been developed enabling the calculation of the forces, torques, and power of the driving motor for different sizes of air springs and various testing conditions. The algorithms that the program is based on and the characteristic results of the calculations are presented. A comparison of energy consumption for the test of one, two, and four air springs is shown. The advantages of the test rig are discussed.
COBISS.SI-ID: 11155227
Because of the randomness of the environment the shape of measured load spectra can vary considerably and therefore simple distribution functions are frequently not sufficient for their modelling. Thus mixed distribution functions have to be used. In general their major weakness is the complicated calculation of unknown parameters. The scope of the paper is to investigate the load spectra growth for actual operating conditions and to investigate the modelling and extrapolation of load spectra with algorithm for mixed distribution estimation, REBMIX.
COBISS.SI-ID: 11155483
The method for modeling cyclic stress-strain-curve scatter for an arbitrary selection of the influencing factors using a hybrid neural network is presented. In an example of the measured data for a high pressure die-cast alloy it is clear that the suggested method is suitable for describing cyclic stress-strain curves. The main advantage of a hybrid neural network in comparison with a conventional method is the neural network's ability to precisely describe the influence of various factors, and their combinations, based on the form and scatter of the cyclic stress-strain-curve families.
COBISS.SI-ID: 10954267
The poor thermo-mechanical properties of polymers can cause deformations, problems with the photometric properties, and sealing difficulties. Deformation prediction was made with standard methods and combined them in a new approach for a quick and efficient evaluation of headlamps. Thin-film RTDs at significant points on the headlamp’s housing are used to measure the temperature. The results were used to determine temperature field for the headlamp’s housing. This temperature field was then used in a finite-element method analysis to determine the deformations in the housing of the headlamp.
COBISS.SI-ID: 10795291