Papers by Keyword: Squeeze Film Damper

Abstract: This paper establishes a linking dynamic model of SFD-sliding bearing rigid rotor system by employing Runge-Kutta method to solve dynamic question of the above systems. The study has shown: rigid rotor system can keep stable periodic motion in a certain scope with the following quasi-periodicity bifurcation.

Abstract: The transfer matrix of rolling bearing including squeeze film damper (SFD) is studied, and the rotor – bearing system is modeled by transfer matrix method of multi-body system. It is proved by an example that the method, which provides a new idea to solve the problem of complex rotor – bearing system, is feasible and effective.

Abstract: A new type of squeeze film damper (SFD) is designed to reduce spool’s impact and vibration which happen in the two-stage larger flow rate high-speed on/off valve with the 450 L/min flow rate and 8ms turn-off time, the valve’s sealing performance、reliability and service life improve largely, and the valve’s response speed doesn’t drop. The simulated and experimental results show: The damper has optimum buffering performance when oil film thickness is 0.1mm, and the spool closing process approach ideal state. The valve will has a great potential application in the powerful occasions because of it's perfect performance: larger flow rate、fast response and novel damper.

Abstract: This paper investigated the variation of dynamical response of a low pressure rotor in turbo-shaft engine with its system parameters. Based on the model of low pressure rotor, a dynamical simplified model of two-disk rotor with Squeeze Film Damper at each end was built. Its motion equations were derived. The numerical method was applied to solve the 12-dimensions differential equations. The influence of some parameters, e.g., rotating speed, eccentricity and its phase angle, mass ratio of two disks, were analyzed. From simulation results, it can be seen that when phase difference of two disks’ eccentricity is π, the two disks have their minimum vibration amplitude respectively. When their phase is identical, their vibration responses reach maximum values. The larger the mass of mid-span disk is, the larger the vibrations of two disks are. When mass of mid-span is lesser than that of overhung rotor, the response of system will decrease.

Abstract: In order to further improve machining quality of superhard materials, it was presented that adds a squeeze film damper on the wheel spindle of ultrahigh speed grinder as a assistant elastic sustain to attenuate the vibration of the wheel spindle. Work principle of squeeze film damper was analyzed; the squeeze film pressure distribution was researched through simulation and damper parameters effect on damping coefficient was studied. Base on the theory research the damper was designed and experiments was done. Experimental result shows the amplitude of the grinding wheel spindle can be reduced 20% and machining quality of superhard materials can be improved 10%～20%. Research works provides a new method for superhard materials machining.

Abstract: For improving grinding quality of ultrahigh speed grinding a new design method for ultrahigh speed grinding spindle is put forwarded based on squeeze film damping technology. Working principle of squeeze film damper of ultrahigh speed grinding spindle is study and differential equations of motion of the ultrahigh speed grinding wheel spindle with a squeeze film damper are set up according to d'Alembert principle. Effects of design parameters of the damper on the motion section of the spindle are studied by the way of simulation based on it. Research works show that the dynamic characteristic of ultrahigh speed grinding spindle can be improved well through adding a squeeze film damper. Research works provides a new technology for the design of the ultrahigh speed grinding spindle system.

Abstract: In order to improve quality of deep hole machining, a new method of deep hole honing based on squeeze film damping technology is put forward. For analysis effect on damper parameters on honing quality, motion differential equation of honing spindle with a squeeze film damper (SFD) is established according to D' Alembert principle and according simulations are studied. Spindle of deep hole honing with a SFD is designed based on the result of simulations and experiments are carried on. Experimental result shows that SFD with reasonable design parameters has excellent damping function to honing spindle, and it can make the vibration of honing spindle reduced 20%～30% and the quality of deep hole machining improved 10%～20%.

Abstract: . In order to improve quality of deep hole finishing, a new method of deep hole honing based on squeeze film technology is put forward. According to fluid lubricates theory, Renault equation of deep hole honing squeeze film damper (SFD) is established, squeeze film force is solved by immense short bearing theory and the effect of the eccentricity of SFD on the damping coefficient is analyzed by MATLAB. Spindle of deep hole honing with SFD is designed based on theory research, and experimental research is carried on. Experimental result shows that SFD with reasonable design parameters has excellent damping function to honing spindle, and it can make vibration of honing spindle reduced 20%～30% and quality of deep hole machining improved 10%～20%.

Abstract: Ultrahigh speed grinding is a kind of high efficient metal cutting method. In order to improve ability of ultrahigh greed grinding wheel spindle to resist vibration and grinding quality, an ultrahigh speed grinding spindle system with a squeeze film damper (SFD) was designed based on the theory of squeeze film damping technology. Pressure distribution and squeeze film stiffness characteristic of SFD was study by the method of simulation. Based on theory study an ultrahigh speed spindle system with a SFD was designed and experiments were done. The study results show that application of SFD technology can effectively restrain vibration which is caused by the imbalance quality when the grinding wheel spindle turning at ultrahigh speed. And the speed of the grinding spindle is higher and the effect of attenuation of SFD to grinding spindle is better. Research works provides a new technology for the design of the ultrahigh speed grinding spindle system.

Abstract: In order to improve the attenuation ability of grinding wheel spindle and manufacturing quality of workpiece, an ultrahigh speed grinding spindle system with a SFD was designed based on the theory of squeeze film damping, and a series of experiments were done. The study results show that the application of SFD technology can effectively restrain vibration which is caused by the imbalance quality when the grinding wheel spindle turning at ultrahigh speed. And the speed of the grinding spindle is higher and the effect of attenuation of SFD to grinding spindle is better. Research works provides a new technology for the design of the ultrahigh speed grinding spindle system.