Temperature influence on dynamic behavior of spacecraft waveguides

Abstract

The lowest eigenfrequency and critical force are important parameters which defines structure behavior under dynamic loading. The paper describes the influence of temperature on the lowest eigenfrequency and critical force of a waveguide straight section in the spacecraft. The straight waveguide modeled according to the beam theory. It has been shown that the temperature change is equivalent an appearance and action of the axial force which makes the structure prestressed and significantly modifies its lowest eigenfrequency. An example of calculation of dependence of the waveguide straight section lowest eigenfrequency on temperature was considered, and it showed the existence of a critical temperature value, where the vibration frequency equals to zero. This critical temperature value corresponds to the loss of waveguide structure stability which is extremely undesirable and requires special methods to avoid such a situation. Stress state of waveguide in case of its loss of stability is also estimated.