32-74 FILTRAREA ŞI CORECTAREA VALORILOR FRECVENŢELOR PROPRII ALE GRINZII DUBLU ÎNCASTRATE EXPUSĂ INFLUENŢEI VARIAŢIILOR DE TEMPERATURĂ
FILTERING AND CORRECTION OF NATURAL
FREQUENCY VALUES FOR A DOUBLE-CLAMPED BEAM
SUBJECTED TO TEMPERATURE CHANGES
This paper presents the effect of temperature changes on the natural frequencies of beams. These may have perfect or elastic restraints at ends. A temperature increase produces compressive stress and consequently a natural frequency decrease. We contrived mathematical relations to evaluate the effect of temperature for the cases of perfect rigid as well as for elastic restraints. If the beam is imperfect, i.e. anisotropic, non-homogeneous or not strength in the initial state, a correction term has to be employed to accurately find the frequencies. The correction method is also presented.
Keywords: natural frequencies, filtering, correction algorithm, temperature
Cuvinte cheie: frecvenţe proprii, filtrare, metodă de corecţie, temperatura