A Study On The Vibration Isolation Characteristics Of An Anti-resonant Hydro-pneumatic Suspension

A novel anti-resonant hydro pneumatic vibration isolation suspension system was presented in this research.Hydro pneumatic suspension is composed of the piston,oil cylinder,oil tube,and air chamber.The air chamber and oil cylinder are connected by the oil tube that contains oil.For the presented suspension system,the dynamic force acted on the vehicle can approach zero at a certain frequency due to the pneumatic spring force can be canceled by the inertial force induced by the fluid motion in the oil tube.Therefore,a very good vibration isolation performance of the presented suspension system can be achieved.The mathematical model of the presented suspension system was derived.In order to solve the non-linear problems,the perturbation method is used.The first harmonic vibration and the second harmonic vibration solution was achieved.For low-frequency vibrations,the anti-resonant hydro pneumatic suspension system can achieve better vibration isolation spectrum which is far better than the traditional hydro pneumatic suspension system.The vibration isolation spectrum of the present model can be widened by adjusting the length and diameter of the oil tube.For the first harmonic vibration,when the length of the oil tube increases as result narrow vibration isolation spectrum can be achieved at lower frequency,as the length of the oil tube decreases,the vibration isolation spectrum became wider at the higher frequency.The diameter of the oil tube is greatly affecting the vibration isolation spectrum.When the diameter of the oil tube decreases the spectrum is becoming wider at the lower anti-resonant frequency.But when the diameter of the oil tube increases then,as a result,we are achieving narrow spectrum vibration isolation spectrum.For the second harmonic vibration,when the frequency increases then the amplitude of the second harmonic vibration decreases.For the high-frequency vibration and lower frequency vibration of the second harmonic vibration can be ignored but at Anti-resonant frequency,the effect of second harmonic vibration cannot be ignored.