On accelerated random vibration testing of product based on component acceleration RMS–life curve

Abstract

Accelerated random vibration testing is usually used to certify a product in random vibration environments. The current certification method is based on the inverse power law and is strictly valid only for Basquin’s type of damage and fatigue of materials. Based on the response spectrum analysis of the product in “the simply scaled accelerated vibrations” and taking the size of acceleration power spectral densities (PSD) the component is undergoing as an index to characterize and compare the damage of the component in different experiments, this paper develops a more practical method in engineering for accelerated random vibration testing of the product in the framework of linear random vibration theory and the rule of acceleration root mean square (RMS)–life curve of the component. The suggested method shows that the time scale is determined by the zero-th and second-order response acceleration spectral moments of the component in real vibration and that simulated in the laboratory, which demonstrates its potential value and advantage in practical application when compared with that based on the von Mises equivalent stress. Simplifications of the method are discussed in detail. In “the simply scaled accelerated vibrations”, the time scale is determined by the acceleration root mean square of the component in real or simulated vibration. It is coincident with the form reported by Allegri but having different physical significance in the case of Basquin’s type of damage and fatigue of the component. The validation experiment with a desk computer was carried out, leading to the verification of the present method.