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Lecture 15 TDH and NPSH. Dr. C. L. Jones Biosystems and Ag. Engineering . Suction Lift. Dr. C. L. Jones Biosystems and Ag. Engineering . Suction Head. Dr. C. L. Jones Biosystems and Ag. Engineering . NPSHR. Dr. C. L. Jones Biosystems and Ag. Engineering .
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Lecture 15 TDH and NPSH Dr. C. L. Jones Biosystems and Ag. Engineering
Suction Lift Dr. C. L. Jones Biosystems and Ag. Engineering
Suction Head Dr. C. L. Jones Biosystems and Ag. Engineering
NPSHR Dr. C. L. Jones Biosystems and Ag. Engineering
NPSH (net positive suction head) Dr. C. L. Jones Biosystems and Ag. Engineering
NPSHA Dr. C. L. Jones Biosystems and Ag. Engineering
NPSHA Dr. C. L. Jones Biosystems and Ag. Engineering
Static Discharge Head • Static Discharge Head = vertical distance from pump centerline to the point of free discharge or the surface of the liquid in the discharge tank. Dr. C. L. Jones Biosystems and Ag. Engineering
Total Static Head • Vertical distance between the free level of the source of supply and the point of free discharge or the free surface of the discharge liquid. Dr. C. L. Jones Biosystems and Ag. Engineering
Total Dynamic Discharge Head • Static discharge head + velocity head at pump discharge flange plus discharge line friction Total Dynamic Discharge Head (TH or TDH) (this is what we design for!!!) • Total dynamic discharge head – total dynamic suction head (tank above suction)…. Or…. • Total dynamic discharge head + total dynamic suction lift (tank below suction) Dr. C. L. Jones Biosystems and Ag. Engineering
Total Dynamic Suction Lift or Head • (fluid below suction) Static suction lift - velocity head at suction + total friction head in suction line • (fluid above suction) Static suction head + velocity head at pump suction flange – total friction head in suction line • Velocity head = energy of liquid due to motion, Usually insignificant Dr. C. L. Jones Biosystems and Ag. Engineering
Total Dynamic Discharge Head (TH or TDH) (this is what we design for!!!) TDH includes friction losses due to piping and velocity Dr. C. L. Jones Biosystems and Ag. Engineering
Example problems Dr. C. L. Jones Biosystems and Ag. Engineering