Control of the Input Signal

The input signal entering the experimental system is actually continuous changes in the concentrations of one or two compounds that are fed to the reactor. However, the concentration profiles of these compounds follow the function described in Section 4.1.2. To achieve the desired concentration profiles in the experimental system, the flow rates of the feed streams are computer controlled. 

In this study the concentration profiles in the feed stream are delineated prior to operation, and these profiles are interpreted in terms of the flow rates of the two entering streams. Thus, the compounds that are fed at variable concentrations are each present in one vessel, and two peristaltic pumps flow these compounds to the reactor. The peristaltic pumps are computer controlled and change their flow rate according to the function in process. 

Control of the peristaltic pumps is achieved using a DT 2811-PGH data acquisition board and a program written for the specific case. The card enables ordering predesigned flow-rate profiles to the pumps and reports the actual 

Using these data the flow-rate profiles are calculated and the information is transfered to the peristaltic pump. 

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