Interested to Buy Any Domain ? << Click Here >> for more details...
what is npsh and how to calculate it for a centrifugal pump
- 15 Answers
- 47811 Views
- Essar, I also Faced
- E-Mail Answers
Answer Posted / saravanan
NPSH is Net Positive Suction Head.. As the name indicates
it is the Positive suction head that should be necessarily
available at suction to prevent the liquid from boil up due
the vapor pressure of the liquid at pumping temperature. It
is also said as the Head necessary at the suction to over
come the vapor pressure of the liquid at pumping
temperature.
Liquid if pumped at low pressure & high temperature (close
to boiling point) nullifies vapor pressure and cavitates.
NPSH available should always be greater than NPSH required
defined by the pump vendor (NPSH R is function of the pump
impeller geometry) to get improved performance.
NPSH available = Suction Pressure - Vapor Pressure + Static
Head - Frictional loss across the suction line.
Since the velocity at the suction is minimum, dynamic head
can be ignored. Hence the only deciding factor is Static
Head, Suction pressure & Operating Temperature..
Higher the static head, higher is the suction pressure &
lower is the pumping temperature better would be the NPSH
avaialble at the impeller eye.
| Is This Answer Correct ? | 37 Yes | 11 No |
Post New Answer View All Answers
What type welding electrode is used to weld chrome?
"When you will install a new piston ring, what will be the position of it?"
Discuss the role of manganese in alloying steels?
HOW MANY PSI CAN REACH THE SCHEDULE 20,40,80 PIPES? GI,BI (CAPACITY OF PIPES)
What is the name given to ratio of actual cycle efficiency and ideal cycle efficiency?
Explain difference between fissile and fertile materials?
What is the temprature used in dearator tank?
What are the different types of fits? Explain
Which types of questions ask in pool campus pune in technical and aptitude test
What type of paper when made into a paper boat floats longest?
why eta(η) became the symbol of Newton law of viscocity
which power station plants r more efficient? which is less? which is most expensive and which is cheapest?
What is the temperature at which diesel normally boils?
If we heat the rod what will happen,draw stress & strain curve before after heating ?
what is procedure of measuring operating length of mechanical seal .(in case of centrifugal pump)?
