RESEARCH ON PULSATION ATTENUATION CHARACTERISTICS OF SILENCERS IN PRACTICAL FLUID POWER SYSTEMS
Keywords:
fluid-borne noise, pressure pulsation, hydraulic silencer, side-branch resonator, insertion loss, noise reductionAbstract
The pulsation attenuation characteristics of silencers in practical fluid power systems are investigated theoretically and experimentally in terms of the insertion loss characteristics, taking the every key circuit-design factors including the pump and the load into consideration, so as to develop an useful CAE design tool for reducing the system audible noise level through the use of a fluid-borne vibration control technique. A new expression for the insertion loss characteristics is also proposed which makes the physical elucidation of its complex characteristics easy and helps to search for the optimum insertion location efficiently. Particular attention has been paid to both the theoretical determination of the optimum insertion location and the op-timum design of silencer for the specified hydraulic circuit. The simulated results of the insertion loss characteristics agree with the experimental results with sufficient accuracy for practical use up to around 5th harmonic of the pump-induced harmonic pressure pulsation. Further, it is shown that our developed new silencer called a “variable-resonance mode type side-branch resonator” has proven to be very successful for reduction of audible noise also in application to a real hydraulic excavator.
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References
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