Simulation Design Of Multi-line Specturm Variable Tuned Water Muffler

In water pipeline system centrifugal pump is the principal noise source, and the operating condition of pump is often changed. In this paper, the author adopts the multi-line spectrum tunable Helmholtz resonator to control the pressure fluctuations in the pipeline system.First, by taking single chamber Helmholtz resonator as a model, the author generalizes the relationship that the structural parameters and the resonant frequency by the method of sound and electricity analogy. Three kinds of resonator models with different structural parameters are built to help the author to obtain its transmission loss and resonance frequency relationship chart through finite element simulation and comes to the conclusion that the changes of the resonator's neck cross-sectional area influence its resonant frequency greatest through comparative analysis of the influence degree of structure parameters on resonator's resonance frequency.After selecting the adjustment on the resonator's neck cross-sectional area as the tunable scheme, this paper designs a tunable resonator structure by combining with the actual processing technology and following the design requirements such as simple structure, small space, less influence on the liquid fluid dynamics in the pipeline.In order to maximize the Helmholtz resonator's silencer band and make up for the shortcomings of the narrow effective silencing frequency range, this paper adopts a multi-cavity resonant silencer design scheme to design the resonator with the characteristics of multi-peak frequency response. The scheme arranged three cavities in a cylinder to achieve attenuation of the pressure fluctuations under different frequency bands at the same time.Furthermore, based on the above theory, the author has optimized the silencer structure, defined the specific resonator parameters and dimensions by the simulation.An experimental study on the semi-active adaptive control algorithm. From the end result, we realize that the effectiveness of algorithm.Finally, to verify the credibility of the simulation design for multi-line spectrum Helmholtz resonator, the author designs Helmholtz resonator test piece, builds the conduit road test bench needed, carries on the silencer performance experiments. Experimental results showed that the experiment and simulation results are basically consistent. It proved this paper's theoretical study and the accuracy of finite element simulation. It is concluded that the design of multi-line spectrum of the Helmholtz resonator is feasible.