Steam Turbine is an important topic with high weightage in GATE examination. In this article we will discuss the important things that must be prepared in Steam Turbines to answer most of the turbine based questions in GATE exam.

 

Free Stimulation Mock Test For GATE 2017
Start Test

What to study in Steam Turbine For GATE

  • Introduction to steam turbine
  • Rankine cycle and modification including superheating, regenerative feed water heating, reheating, etc.
  • You should also prepare the classification of turbines based on blade profile, impulse and reaction turbines.
  • Velocity diagrams are very important, you will find one question in GATE based on this topic.
  • Numericals are very important. 1 Question will be surely asked on this section.

Also read : Best Books for GATE ME by Toppers

Questions From Gate

Ques 1 :

What happens when reheater  is incorporated in a steam power plant?

P : Thermal efficiency of the plant always increases.

Q : The dry fraction of steam at condenser inlet always increases.

R : The mean temperature of heat addition always increases.

S : The specific work output always increases

(A) P and S

(B) Q and S

(C) P, R and S

(D) P,Q,R and S

 

Answer:

B is the right answer because Reheater always increases the dryness fraction of steam at condenser inlet and always increases the specific work output.

Also read : how to prepare casting for GATE

Free Stimulation Mock Test For GATE 2017
Start Test

Ques 2 :

Assume the given turbine to be a part of Rankine cycle. The density of water at the inlet to the pump is 1000 Kg/m3.ignoring the K.E.and P.E. effects, the sp. work (in KJ/Kg) supplied to the pump is

 

(A) 0.293

(B) 0.351

(C) 2.930

(D) 3.510

 

Answer :

C

Explanation

Pump work
hinlet + q = houtlet + Wpump

Here, q=0

Wpump = hinlet - houtlet

W = ∆hpump

Reversible adiabatic

dq=dh-Vdp

dh=Vdp

dhpump =V(p2 – p1)

= 1/ρ(3000 – 70) kPa

= 2.930 kPa

Free All India Test Equipped with Artificial Intelligence

Start Test  

Alternative method :


V = m/ρ = 1/1000 kg

Pump work = (p1 – p2)V

= (3 x 103 – 70)/1000 KJ/Kg


= 2.930 KJ/Kg

must read : Most Important Topics For GATE-2017 (ME) || Guaranteed Results

Best Wishes !!

 

What aspirants need is the right approach along with concrete strategies to reach their goals. GATE GUARANTEE PACK has been the choice of successful GATE toppers all over India. 

It is the perfect online tool to check your level of preparedness among st students preparing all over the country where you study under guidance of mentors.

 

 

Search on PrepLadder