Chemical Engineering Answers

Which of the following control systems can be adopted for the pure capacitive process

a. Adaptive control system

b. Feed forward control systems c. Feed backward control systems

d. None of these

Draw the Bode plots for Proportional Integral Derivative controller, transportation lag and first order system.

The transfer function of the process, a measuring element and a control valve is given respectively byGp =4/4S+1,Gm=2/2S+1 and Gv=1.5/4S+1. A proportional controller with gain one is used. Find the steady state error for step change of magnitude 3 in the set point. Determine the stability of the process using Routh- Huwritz criteria. If unstable, find two roots that lie on the right hand side of imaginary axis.

Explain about Inverse response with an example,

A step change of magnitude 10 is introduced into the transfer function

Y(S)/X(S)= 4/(2S²+0.3S+0.5),

find the following

a. Percent overshoot.

b. Rise time

c.Maximum value of y(t)

d. Ultimate value of Y(t)

e. Period of oscillations.

Explain different time integral performance criteria and their applications.

Consider a control system with the open loop transfer function is Gol =Kc e^{-0.36S}/12S+1 the pre factor S in minutes and Kc, is the gain of the controller. The frequency for phase. margin of 30° is 4.04 rad/min; find the value of the gain of the controller for a gain margin of 2. °

Write the differences between feedback control process and feed forward control process?

The tank of volume 0.25 m^3 and height of 1m has water flowing at 0.005 m^3/min the outlet flow rate is governed by the linear relation Fout-0.1h, where h is the height of the water in the tank in m and Fout is the outlet flow rate in m^3/min. The inlet flow rate. changes suddenly from its nominal value of 0.05 m^3 min to 0.15 m^3/min and remains there. Find the time in minutes at which tank overflows.

Check the stability of the closed system whose characteristic equation is given by S^4 +4S³+6S² +2s+3=0.