Pump efficiency calculated w/ temperature increase of liquid in pumps
Pump efficiency calculated w/ temperature increase of liquid in pumps
(OP)
I am looking for technical article in books or magazines giving details of meassuring and calculation of pumps efficiency by the temperature increase if liquids passing through pumps.
Can any body help me ?
Paul Warneke
Can any body help me ?
Paul Warneke





RE: Pump efficiency calculated w/ temperature increase of liquid in pumps
Temp Rise = H(1.0-E)/(778*EU)
Where H = Total head in feet
E = Efficiency of the pump
U = Specific heat of the pumped liquid in BTU/lb*Deg. F
All you do to get to this equation is take the power of a pump:
P (in hp) = TDH*GPM*S.G./(3960*Eff.)
That is how much power the pump needs to pump the fluid. Then assume an eff. of 1.0, this is the power need to pump the fluid if the pump were a perfect machine. The difference is the amount of power lost by other means (heating the fluid up and sound). If you assume the power required to make noise insignificant, then you can make the assumption that all of that lost power is transferred into heat.
Hope this helps.
RE: Pump efficiency calculated w/ temperature increase of liquid in pumps
RE: Pump efficiency calculated w/ temperature increase of liquid in pumps
At a pump conference in London, I found this empirical formular developed in the South African mining industry, and have changed it into SI units. It applies for water at up to 54 degC:
Efficiency = 100/ [1- (0.003(t -2) + 4160 (TR/TH)] where t is the inlet water temperature, degC, and TR is temperature rise. C deg, and TH is total Head, kPa
I have tried this on high pressure pumps and high water temperatures, and when steam tables are used the results are close.
Mechanical losses are not included, but these are insignifcant for any but very small pumps.
RE: Pump efficiency calculated w/ temperature increase of liquid in pumps
Maurice Yates' articles are a very good resource as well.
We are using his rig, which is practical only above about 200 HP, for measuring our water system pump efficiencies, and would welcome any discussion on it's methods and uses.