Research on Non-sinusoidal Vibration Excitation in Particle Impact Noise Detection

Particle impact noise detection (PIND) test is a kind of reliability screening technique which is used to detect free particle in hermetical components and is specified in MIL-STD-883E method 2020.7. But sinusoidal vibration excitation is merely used to drive vibrator that doesn´t always makes the particle´s energy increase though recovery coefficient is equal to one. Two kinds of non-sinusoidal excitations are used to drive vibrator. For sawtooth vibration excitation, it derives the upper limit frequency and the lower limit frequency, accordingly obtains test conditions which are necessary and sufficient conditions, and proves that the particle´ energy will increase when recovery coefficient is close to one based on dynamics. Exponential vibration excitation is also researched in the same way and the similar results are gained. Comparing to sinusoidal vibration excitation, these two kinds of vibration excitations insure the particle will collide with the upper wall without fail under obtained test conditions. Some simulations are given last