Document Type
Thesis
Date of Award
6-30-1962
Degree Name
Master of Science in Chemical Engineering - (M.S.)
Department
Chemical Engineering
First Advisor
Herbert Dengler
Second Advisor
Jerome J. Salamone
Third Advisor
Joseph Joffe
Fourth Advisor
Michael Frederick
Abstract
Stability and response of automatically controlled liquid level systems was investigated theoretically by transient and frequency response analysis and experimentally on a laboratory liquid level system.
Transfer functions were derived for each component and were used to describe the response of the experimental system. The effect of measurement time constants on system performance was experimentally investigated. Poor control, but not instability, resulted from an increase in measurement time constant. The behavior of the system at various operating loads was determined experimentally. The system was unstable at the maximum measureable flow rate, but stable at all other loads. Theoretical response curves did not show an unstable system at the maximum inlet flow rate, but did show cycling above 70% of the maximum inlet flow rate. This tendency towards cycling and control valve characteristics caused the system to become unstable.
The investigation showed that it is necessary to carefully match system load and control valve operating characteristics to insure good control of commercial installations.
Recommended Citation
Rosen, Milton Kalman, "The stability and response of an automatically controlled liquid level system" (1962). Theses. 3240.
https://digitalcommons.njit.edu/theses/3240
