MICROFICHE REFERENCE LIBFUUW - Cd3wd.com

160Example 6.2 - Continuedd) Approximate discharge = (18.33 ft-lb/set) f (624ft-lb/ft3) = 0.03 ft3/sec = 13.5 gpnl.e) Water required = 33.3 in. x 0.5 ac. = 16.7 acre-in. =450,000 gallons (U.S.).f) Time required =450,000 gal x 1 hr13.5 gpm 60 min= 556 hoursi.e., this is less than the 5 hr/day working limitover the 120 day season.3. Food required to generate energy:a) To work at 2200 ft-lb/min with a 20% efficiency,requires man to have an energy input =2200 x 60= 660,000 ft-lb/hr.0.20which at 3087 ft-lb/calorie ,= 214 cal/hr.b) In 556 hours of pumping, the worker will use556 x 214 = 118,000 cal.c) At 1814 calories per lb of rice, this is equivalent to118,000= 66 lbs of rice.1814d) This energy input of rice required for the liftingof water is thus about 2.5% of the expected 2,600 lbyield.These examples of cost analyses have been presentedto illustratetheir use in the selection of water lifters and prime movers. When coordinatedwith water requirement, availability, and adaptability considerations, such analyses become part of a systematic approach for efficientlymatching water lifter and driver to a given application.