529
OF ENGINEERING FOKMULÆ.
Animal Powkh.
Working 8 hours I» lbs. raised
per day. 1 ft. per min.
Horse..........21,000
Ox_______________12,000
Mule __________10,000
Ass ..........3,500
Working 8 hours In lbs. raiseri
p‘r day. 1ft. per mill.
Man, as in rowing .4000
Ditto on tread-wheel 3100
Turning a handle ,. 2600
WATER-POWER.
Theoretical Hobse-poweb of Water.
Q = Quantity of water in cube feet per minute.
h — Head of water from tail-race in feet.
P = Theoretical horse-power.
P = *001892 Q h. Q = 528‘'I1'
Effective Horse-powek for Diffekent Motors.
Theoretical power being ., .. ^1-00
Undershot water-wheels .. .. = -35
Poncelet’s undershot water-wheel = • 60
Breast-wheel..................= -55
High-breast .. ,, . .. .. = -60
Overshot wheel ..............= -68
Turbine......................= -70
Hydraulic ram raising water .. • 60
Water-pressure engine......... 80
Undershot Water-wheel.
Velocity of periphery of the undershot water-
wheel should equal the theoretical velocity due to
the head of water x 0'57.
Or = -57 V. For values of V, see Table of
theoretical velocity of water.
h = Head of water in feet.
Q = Quantity of water in cube feet per minute.
P = Effective horse-power.
, 1511P
Q = —7------ P= -00066 QÅ.
h
2 M
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