A surge tank system is to be installed as part of a pilot plant facility. The initial proposal calls for the configuration shown in figure. 4.3. Each tank is 5 ft high and 3 ft in diameter. The design flow rate is q1 = 100gal/mm. It has been suggested that an improved design will result if the two tank system is replaced by a single tank that is 4 ft in diameter and has the same total volume (i.e., V= V1 + V2).

(a) Which surge system (original or modified) can handle larger step disturbances iii qi? Justify your answer.

(b) Which system provides the best damping of step disturbances in q1? (Justify your answer). In your analysis you may assume that:

(i) The valves on the exit lines act as linear resistances.

(ii) The valves arc adjusted so that each tank is half full at the nominal design condition of qt 100gal/min.