Comparison of two mechanical windmills for pumping water

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:269385

Clark, R N ^[1]

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1. USDA-Agricultural Research Service, Bushland, TX (United States)

A comparison of two mechanical wind pumping systems was carried out to determine windmill performance at different water depths. A 2.44 m (8 ft) rotor diameter windmill with 15 vanes, and a 4.88 m (16 ft) rotor diameter windmill with 32 delta wing vanes, were compared. The smaller windmill had vanes that filled 90% of the rotor area while the vanes on the larger one filled 41% of the rotor area. The smaller unit used a gearbox and the larger one used a pump jack style with a counter weighted shaft. Results from this study showed that both windmills started pumping at about the same wind speed (2.5 and 3.5 m/s), but the larger rotor operated at 6 to 8 strokes per minute faster than the smaller system when wind speeds were between 4 and 1 0 m/s. Although both windmills were fitted with the same size and style of pump, the larger rotor pumped more water because it had more stokes per unit of time. The delta wing rotor averaged 14,874 L/day compared to 10,974 L/day for the traditionally designed rotor. However, one must consider the difference in rotor diameters, total weight, cost and the efficiency of the two units. The larger rotor had a peak efficiency of 6.5% compared to 10.5% for the smaller rotor. The 35% more water pumped required twice as much rotor diameter.

• Research Organization: American Wind Energy Association, Washington, DC (United States)
• OSTI ID: 269385
• Report Number(s): CONF-950309--; ON: DE96011159
• Country of Publication: United States
• Language: English

Related Subjects

17 WIND ENERGY
COST
EFFICIENCY
FLOW RATE
PERFORMANCE
ROTORS
VANES
WATER PUMPS
WIND POWER