Research On The Allowable Range Of Stiffness Error Of Nonlinear Energy Sink

With the continuous development of vibration absorbers,many spring-type damping structures have been developed one after another and are widely used in various fields of production and life.During the use of the spring-based nonlinear energy sink structure,there is always an error in the stiffness of the spring inevitably.If the impact of the error on the vibration absorption efficiency of the vibration absorber cannot be explored and corresponding measures are taken,the damage to the structure is immeasurable.Therefore,the study of the allowable range of stiffness error is a very realistic subject.In this paper,the stiffness error tolerance range of purely nonlinear energy sinks and non-smooth nonlinear energy sinks are studied,and the influence of the spring in the vibration absorber on the vibration absorption efficiency of the vibration absorber under tension or compression is studied respectively.The content of the paper can be summarized as follows:The failure of the single-degree-of-freedom nonlinear energy sink is studied when there is a small deviation in the realization of pure cubic stiffness.The effect of positive or negative linear stiffness due to installation errors on the vibration absorption efficiency of nonlinear energy sinks is quantitatively studied.The vibration absorption efficiency of the series two-degree-of-freedom vibration absorber spring with stiffness error was studied,and then the stiffness coefficient of the spring was changed,and then the influence of the stiffness error of springs with different stiffness coefficients on the vibration absorption efficiency of nonlinear energy sink was explored.Aiming at the recently discussed piecewise nonlinear energy sink,the allowable range of stiffness error is studied.Under the impact load,change the value of the pre-tension or pre-compression of the first or second spring to obtain the vibration absorption variation law of the shock absorber,so as to judge the allowable range of stiffness error.Under the simple harmonic excitation amplitude,change the value of the spring pretension of the first section or the second section,observe the vibration absorption performance of the vibration absorber,and obtain the change law of its vibration absorption performance,so as to judge the allowable range of stiffness error of the piecewise nonlinear stiffness energy sink.Based on the research on the allowable range of stiffness error for piecewise nonlinear energy sink,this paper proposes a study on the allowable range of stiffness error for pure-strong nonlinear energy sink.Only the first section of the spring in this structure has a purely nonlinear stiffness.Under the impact load,change the stiffness of the second section of spring and the gap distance between the second section of spring and the vibration absorber mass block,so as to study the second section of spring with different linear stiffness and different gap distances,when the first section of spring has stiffness error,the change law of the vibration absorption efficiency of the vibration absorber,so as to judge the allowable range of the stiffness error.Under the harmonic excitation amplitude,the stiffness of the second spring is fixed,the gap distance is changed,and the first spring has a pretension,the vibration absorption performance of the vibration absorber is analyzed to determine the allowable range of the stiffness error of the pure-strong nonlinear energy sink.