Rainy FL-80, Руководство пользователя

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1 square meter of area at the rate of 25.4 mm precipitation of rainfall, the collection of
water=25.43 liters, therefore, 1 acre of area (43560 sq.ft or 4050 sq.m) yields
103012.36 liters of water.
Considering 100 square meters of roof area.
Roof area in square meter x coefficient of friction of roof x filter efficiency x
rainfall in mm = water in liters.
Evaporation, friction and absorption of water by the roof etc.
Usually 15 to 25% loss of water will be occurred depending upon the type of roofs.
It depends upon the type of filter and manufacturer’s guarantee on
performance and efficiency of filter
Per day s highest rainfall or per year s average rainfall to be
considered.
Roof area-100 sq.m, Coefficient of friction-0.85%, Filter Efficiency-90%, Average
Rainfall/year considered 1000 mm.
100x 0.85x 0.90 X 1000= 76500 liters
Size of the water storage tank can be decided based on the roof area available for
harvesting the rainwater while considering either highest rainfall per day or 5% of
average annual rainfall. For the above said area the ideal tank capacity would be 5000
liters.
While calculating the sizes of water tanks, filter, rain gutters, down take pipes etc.
it is suggested to assume 20% higher capacity than the original value in order to round
off the error and to accommodate slight tolerance range.
Example:
Calculation:
Coefficient of friction:
Filter efficiency:
Rainfall in millimeter: ’ ’
To calculate the required tank size:
Note:
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