Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Summer 5th Sem 2150504 Instrumentation And Process Control Previous Question Paper

Enrolment No.___________

**GUJARAT TECHNOLOGICAL UNIVERSITY**

**BE - SEMESTER? V EXAMINATION ? SUMMER 2020**

**Subject Code: 2150504**

**Date:02/11/2020**

**Subject Name: INSTRUMENTATION & PROCESS CONTROL**

**Time: 02:30 PM TO 05:00 PM**

**Total Marks: 70**

**Instructions:**

**1. Attempt all questions.**

**2. Make suitable assumptions wherever necessary.**

**3. Figures to the right indicate full marks.**

**MARKS**

**Q.1 (a)**Distinguish among step, exponential, sine and ramp forcing

**03**

functions.

**(b)**Discuss the comprehensive comparison of time constant of first

**04**

order systems: Mercury thermometer, liquid leven in single

tank & mixing process.

**(c)**Prove that "Response of Noninteracting tanks always result in

**07**

an overdamped or critically damped second-order system and

never in an underdamped system"

**Q.2 (a)**Compare the step response and nature of roots of second order

**03**

system.

**(b)**With Inversion by partial fractions prove that

**04**

dX + X = 1

dt

**(c)**A step change of magnitude 4 is introduced into a system

**07**

having the transfer function

Y(s)

10

=

X(s)

S2 + 1.6S + 4

Determine

(a) Percent overshoot

(b) Rise time

(c) Maximum value of Y(t)

(d) Ultimate value of Y(t)

(e)

Period of oscillation

OR

**(c)**A thermometer having a time constant of 0.2 min is placed in a

**07**

temperature bath, and after the thermometer comes to

equilibrium with the bath, the temperature of the bath is

increased linearly with time at a rate of 1o/min. What is the

difference between the indicated temperature and the bath

temperature

(a) 0.1 min

(b) 1.0 min after the change in temperature begins?

**Q.3 (a)**Discuss the rules for convert close loop block diagram into

**03**

single transfer function.

**(b)**Derive the transfer function of distance velocity lag.

**04**

1

**(c)**Derive the transfer function of second order U tube manometer

**07**

& step response for critically damped.

OR

**Q.3 (a)**Differentiate between Negative Feedback and Positive

**03**

Feedback with suitable examples of each.

**(b)**Differentiate between Servomechanism type problem and

**04**

Regulator problem.

**(c)**Determine the transfer function Y(s)/X(s) for the block

**07**

diagram shown in Fig.

**Q.4 (a)**Derive the transfer function of PI control.

**03**

**(b)**Discuss the advantages and disadvantages for P, PI & PID

**04**

control for feedback control system.

**(c)**The open loop transfer function of a certain control system is

**07**

defined as

Kc

G(s) =

s

s

(s + 1) [(2) + 1] [(3) + 1]

Determine the value of Kc for which the control system is

stable by using Routh test for stability. And For the value of Kc

for which the system is on the threshold of instability,

determine the roots of the characteristic equation with the help

of routh test theorem 3.

OR

**Q.4 (a)**Derive the transfer function of PID control.

**03**

**(b)**Explain linear system versus non-linear system.

**04**

**(c)**Explain Nyquist stability criteria.

**07**

**Q.5 (a)**Discuss the principal of measurement in Bimetallic

**03**

Thermometer.

**(b)**Discuss the various elements of an Instrument.

**04**

**(c)**Ex

plain the principal, construction and working of radiation

**07**

pyrometer.

OR

**Q.5 (a)**Discuss the principal of liquid level measurement in bubbler

**03**

system.

**(b)**Discuss the various types of pressure springs which used in

**04**

thermometer.

**(c)**Explain the principal, construction and working of bellows

**07**

differential-pressure gauge.

*****************

2

This post was last modified on 04 March 2021