MICROFICHE REFERENCE LIBFUUW - Cd3wd.com
MICROFICHE REFERENCE LIBFUUW - Cd3wd.com MICROFICHE REFERENCE LIBFUUW - Cd3wd.com
23Vapor Pressure (P,)Suction Friction Losses (HF)VelocityHead II-i,)-c.-J0.-+0GI- ---Figure 2.2 Net positive suction head (NPSH)
24whereyWis the specific weight of water and K is a constant whichdepends on the unitsof measurement used for the other terms.Of course, since water lifting devices like any other machinery havelosses (e.g., internal friction, slippage, leakage, etc.), in order toadd a given WHP to the water, some higher brake horsepower (BHP) willhave to be applied to the pump. This BHP will be the energy which mustbe delivered to the pump by its prime mover. It should be noted herethat this parameter of power is not limited to mechanical prime movers, butthat manual and animal BHP can be determined to evaluate the performanceof water lifters utilizing such mears of motivation.2.2.4 Efficiency (Eff)The efficiency of a water lifter is the ratio of energy added to thewater over the energy put into the device to obtain the increase in waterenergy,or put in terms of power,WHPEff=m . (2.15)An efficiency can also be calculated for the prime mover which suppliesthe BHP to the water lifter. Where the method of transmitting this primemover power (BHP) to the water lifter is not direct, losses may alsooccur in the transmission. For example, when belts are used between amotor and pump, slippage and heat losses occur which prevent getting allthe motor’s output power to the pump. Thus, an efficicney for the trans-missioncan also be calculated.
- Page 1: MICROFICHEREFERENCELIBFUUWA project
- Page 4 and 5: TABLE OF CONTENTS:.LIST OF FIGURES
- Page 6 and 7: LIST OF FIGURES (CONT)Figure3.163.1
- Page 8 and 9: LIST OF TABLESTable2.12.2a2.2b3.13.
- Page 10 and 11: 2find both new water lifting device
- Page 12 and 13: 4During the 3rd centuryB.C., Archim
- Page 14 and 15: GIn 1698, Thomas Savery obtained a
- Page 16 and 17: 9the United States was starting set
- Page 18 and 19: 11engines, motors, transmissions, e
- Page 20 and 21: Chapter 2Water LiftingPrinciples2.1
- Page 22 and 23: 15Table 2.2a Classification of wate
- Page 24 and 25: 2.2.1 Discharge or Capacity (Q)Disc
- Page 26 and 27: (h) Drawdown (D) is the vertical di
- Page 28 and 29: 21Tota I DynamicHeadI Total Static
- Page 32 and 33: Multiplying all these efficiencies
- Page 34 and 35: 27NPSHR-Q, is also usually included
- Page 36 and 37: 3.2.1.1 Bucket/BagUtilizing nothing
- Page 38 and 39: handmade construction can be easily
- Page 40: animal is returning to the top, the
- Page 43 and 44: 363.2.1-S Counterpoise LiftThe coun
- Page 45 and 46: 38to return the lever. Combinations
- Page 47 and 48: 40Table 3.1Shadouf performanceLift
- Page 49 and 50: (b)Figure 3.5 Scoop (a) used as sho
- Page 51 and 52: ‘PIVOT-r- ----hFigure 3.6 Wzcer b
- Page 53 and 54: 46water. The capacity of this devic
- Page 55 and 56: - =7?=PIVOTCOUNTER WEIGHT\FLAP- VAL
- Page 57 and 58: 50(a)ROLLER 7- HAND RAIL/SIDE - BY-
- Page 59 and 60: 52flow in through a check-valve (e.
- Page 61 and 62: 54exhaust valves for the steam (or
- Page 63 and 64: 56Another significant difference be
- Page 65 and 66: 58shaft), two other forms of these
- Page 67 and 68: 60Among the simplest designs for a
- Page 69 and 70: 62/HANDLEBARDISCHARGEHOSEfFOOTRE$TD
- Page 71 and 72: HANDLE/CONNECTINGARMDISCHARGEFLAP V
- Page 73 and 74: 663.3.1 WheelAfter many of the earl
- Page 75 and 76: 68Table 3.2 Manually-operated paddl
- Page 77 and 78: 70engine (2-3 hp) as the prime move
- Page 79 and 80: 72Table 3.3 records some of the per
24whereyWis the specific weight of water and K is a constant whichdepends on the unitsof measurement used for the other terms.Of course, since water lifting devices like any other machinery havelosses (e.g., internal friction, slippage, leakage, etc.), in order toadd a given WHP to the water, some higher brake horsepower (BHP) willhave to be applied to the pump. This BHP will be the energy which mustbe delivered to the pump by its prime mover. It should be noted herethat this parameter of power is not limited to mechanical prime movers, butthat manual and animal BHP can be determined to evaluate the performanceof water lifters utilizing such mears of motivation.2.2.4 Efficiency (Eff)The efficiency of a water lifter is the ratio of energy added to thewater over the energy put into the device to obtain the increase in waterenergy,or put in terms of power,WHPEff=m . (2.15)An efficiency can also be calculated for the prime mover which suppliesthe BHP to the water lifter. Where the method of transmitting this primemover power (BHP) to the water lifter is not direct, losses may alsooccur in the transmission. For example, when belts are used between amotor and pump, slippage and heat losses occur which prevent getting allthe motor’s output power to the pump. Thus, an efficicney for the trans-missioncan also be calculated.
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