Mathematical modeling of the sensitivity of natural vibrations of structures, taking into account rotation and heating

Oleg V. Repetckii, Dinh Cuong Hoang

Irkutsk State Agrarian University named after A.A. Ezhevsky

In this work, mathematical models have been developed and the sensitivity of plate vibrations has been tested taking into account rotation, heating with the extension of numerical analysis to radial wheels of turbomachines. First, the influence of the linear and quadratic law of temperature change on the static and dynamic characteristics of the plate was studied using the BLADIS + and ANSYS programs. These results of the calculation of natural frequencies are consistent in two programs and with an analytical solution. During the calculation, it is noted that the natural frequencies of the plate decrease with a quadratic law of temperature change, but increase with rotation. To understand the effect of rotation and heating on sensitivity using the program SOLIDWORKS, ANSYS WORKBENCH, and MATLAB simulate vibration modes and their sensitivity to changes in the studied frequencies. From the results of testing the plate, which showed good convergence of the calculation of natural frequencies, it was decided to extend the created mathematical models and software packages to the real radial wheels of turbomachines. This cover disc is characterized by the greatest degree of deformation, taking into account rotation. And the zone of reduction in vibration frequencies decreases at the upper edge of the blades, but increases in the middle of the leading edge of the blades, taking into account rotation and uneven heating. Thus, the obtained calculations of the analysis sensitivity on the plate and the real radial wheel, taking into account rotation and heating make it possible to reduce the volume of expensive experimental studies and reduce the time for designing new machines according to the criteria of efficiency, reliability, technology and resource saving of highly loaded machine units.

finite element model, reliability, plate, radial wheel, turbomachine, frequency vibration, sensitivity