Development of an Active Attenuator for Pressure Pulsation in Liquid Piping Systems. 5th Report. Trial Construction of the Adaptive Control System and Fundamental Experiments.

Abstract

A new technique for an active adaptive attenuator for wide-band pressure pulsation in liquid piping systems, which controls feed-forwardly the second source by the progressive wave component of fluid-borne vibration detected at the upstream of the pipeline and has the capability to change system parameters owing to a programmable digital filter, is presented together with computer simulation and experimental results. The adaptive feed-forward control structure is based on the so-called "Filtered-X LMS algorithm". It is established by the test in the small-sized model experimental pipeline that the pressure pulsation in a downstream pipe of the second source can be reduced to at least -20 dB for almost all harmonics of around 10 to 800 Hz, while maintaining the stability, even in the case where uncontrolled system parameters such as acoustic properties, dynamic characteristics of second source, etc., change with time. It is also shown that the computer simulation agrees well quantitatively with the experimental results and can be applied successfully to system design.