DEVELOPMENT OF DESIGN METHODS FOR RESONANT THIN-WALLED CYLINDRICAL STRUCTURES OF ON-BOARD ELECTRONIC SYSTEMS
Background. The basis of the load-bearing structures of on-board electronic systems (OES), as well as many other engineering products, are thin-walled elements - rods, plates, shells, which should provide the necessary strength, stability and rigidity of the structure under given weight restrictions. At the same time, the choice of design margins for all performance parameters of elements of such structures (safety factors, safety margins) should ensure reliability equal to or higher than the required one, which can be achieved by creating resonance-free structures in a given vibration frequency range. The aim of the work is to develop an engineering methodology for calculating the necessary margin for detuning the natural frequency of oscillations and its practical use. Materials and methods. The paper uses the provisions of the theory of mechanical vibrations to obtain analytical expressions for the natural vibration frequency of a cylindrical shell. For the numerical solution, finite element methods and the ANSYS software package are used. Results. The results of calculations of the natural frequency of vibrations of thin-walled structures of on-board radio-electronic equipment are proposed, which make it possible to reasonably select the dimensions of the structure in terms of protection against Numerical solutions of test problems are performed using the ANSYS software package, conclusions are drawn and recommendations are given for the creation of resonance-free in a given vibration frequency range of thin-walled structures of on-board radio-electronic equipment units in the form of circular barrels. Conclusion. The results of the work are presented in the form of recommendations for determining the main natural vibration frequencies of casings in the form of circular barrels and choosing design solutions for creating non-resonant structures at the early stages of designing.