Mechanical Engineering - Steam Nozzles and Turbines - Discussion

9. 

In a nozzle, whole frictional loss is assumed to occur between

[A]. inlet and thoroat
[B]. inlet and outlet
[C]. throat and exit
[D]. all of these

Answer: Option C

Explanation:

No answer description available for this question.

Sakthi said: (Sep 27, 2013)  
Most of the frictional loses occurs between the throat and exit because both the length as well as velocity is higher.

Gokul said: (Dec 9, 2013)  
I not clear but during convergence and divergence the reaction b/w the fluid and nozzle is higher so they must be considered.

Gaurav Verma said: (Aug 27, 2014)  
Because between to throat and exit in high pressure than low velocity.

Japee said: (Aug 27, 2014)  
How's that possible because first in convergent part friction should more and then it should less.

Saddam Husain said: (Nov 4, 2016)  
Because at throat and exit the shape of nozzle changes. Therefore it resists.

Vijay Prajapati said: (Dec 22, 2016)  
Friction losses occur b/w throat and exit because in this section velocity will increase.

Nakul said: (Jan 21, 2017)  
Yeah, flow at the inlet is at very high speed so frictional losses can be neglected and also the frictional losses depend upon the Mach no.

Phani said: (Sep 8, 2017)  
As there is contact between steam and nozzle surface through out the length nozzle there is friction loss from inlet to outlet.

Rahul said: (Oct 15, 2018)  
Basically, the velocity is high and the length of the divergent portion is more than (3-4 times longer) convergent side.

Prasad Cln said: (Jun 24, 2020)  
At the inlet i.e. the convergent portion of the nozzle, the stem velocity is very low (subsonic) as compared to the other 2 sections i.e throat (sonic) and a divergent portion (supersonic).

This continuous increase in velocity is obtained by-.

1) due to convergence of the nozzle diameter at the convergent section (inlet to throat) -subsonic to sonic.

2) due to the divergence of the nozzle diameter after the throat- the pressure tries to increase, but the pressure rise is overthrown by the friction between the walls of the nozzle and steam. Thus the velocity of the steam increases. From sonic to supersonic.

Hence the right answer will be the "throat and exit".

Patel Uvesh said: (Dec 26, 2020)  
Because tha length of convergent part is much higher.

Patel Uvesh said: (Dec 26, 2020)  
Because tha length of convergent part is much higher.

Post your comments here:

Name *:

Email   : (optional)

» Your comments will be displayed only after manual approval.