Question

(a) Develop a transfer function that relates the concentration c2 in tank 2 to the concen tration x in the feed, that is, C2 (s)X(s) where C2 and X are deviation variables. For convenience, assume that the initial concentrations are x-C20 (b) If a unit-step change in x occurs, determine the time needed for c2 to reach 60 percent of its ultimate value for the cases where α--0, 1, and oo. (c) Sketch the response for α-00. Assume that each tank has a constant holdup volume of 1 ft3. Neglect transportation lag in the line connecting the tanks and the recirculation line. Try to answer parts (b) and (c) by intuition

Answer 1

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