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Fluid Mechanics Lab: Positive Displacement Pumps. ENTC - 303. Objectives. To gain an understanding of the types of positive displacement pumps, their working principle, design and construction. 2. To determine the performance characteristics curves of a positive displacement vane pump.
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Fluid Mechanics Lab:Positive Displacement Pumps ENTC - 303 PROF. ALVARADO
Objectives • To gain an understanding of the types of positive displacement pumps, their working principle, design and construction. 2. To determine the performance characteristics curves of a positive displacement vane pump. PROF. ALVARADO
Pumps Classification From www.pumpschool.com PROF. ALVARADO
Positive Displacement Pumps • Positive displacement pumps have the capability of providing a fairly constant flow rate over a wide range of pressures. • The pump delivers a fixed volume of liquid with every rotation of the input shaft PROF. ALVARADO
Positive Displacement Pumps Internal Gear Pump External Gear Pump Vane Pump Circumferential Pump Flexible member Pump Lobe Pump Figures from www.pumpschool.com PROF. ALVARADO
Positive Displacement Pumps vs. Centrifugal Pumps • Positive Displacement for (this week): • High viscosity • Exact flow for different pressures • High pressures • Centrifugal (next week): • Low viscosity • High flows • Applications requiring a range of flows. PROF. ALVARADO
Positive Displacement Pumpsvs. Centrifugal Pumps PROF. ALVARADO
Positive Displacement Pumps vs. Centrifugal Pumps PROF. ALVARADO
Pump efficiency • The overall pump efficiency is a product of the volumetric efficiency and the mechanical efficiency PROF. ALVARADO
Pump efficiency (P is in Pa; QA and QT are in m3/s; T is in N-m; N is in RPS)
Pump efficiency Overall Efficiency = Vol.Efficiency x Mech.Efficiency Actual Power Out = P x QA Actual Power In = Electrical Power Input (Watts) PROF. ALVARADO
References • www.pumpschool.com • Fluid Power with applications, Anthony Esposito. PROF. ALVARADO