DACL System Dynamic Performance. I: Response‐Prediction Analysis

Abstract

This paper examines the dynamic performance of the dual‐acting controlled‐leak (DACL) system for automating radial gate control. The dynamic performance of the DACL open‐channel level‐control system has been analyzed using classical linear control theory to facilitate the design of such systems to meet specific performance criteria. The mathematical analysis predicts that in normal closed‐loop operation, the system behaves like a second‐order control system. The response to disturbances is therefore a function of the system's natural frequency and damping ratio. Explicit expressions for the frequency and damping ratio were obtained in terms of system design parameters, and a design value of the damping ratio was recommended for optimal response in similar DACL systems. The analytical model was verified by tests conducted on a laboratory model arranged for downstream control. The results of these tests are presented in a companion paper.