Document ZBaB9qNeEDY63Ve2Enp6p79VV
HEATING VENTILATING AIR CONDITIONING GUIDE 1943 Thermal transmission (heat transferred per unit time)
Thermal resistance (degrees per unit of heat transferred per unit time).
R
=
ti
--_ti
~
L
~kA
Thermal resistivity..
____________ 1/k
Vaporization values at constant pressure, Differences between values for saturated
vapor and saturated liquid at the same pressure:Subscript f*
Velocity-_________________ __________ ____ _________ ________ _y
Volume (total)______________________;___________ __________________ _v
Volume per unit time. Rate at which quantity of material passes through a
machine, Quantity of heat per unit time, Quantity of heat per unit weight--;__ ...q
Watt__.:____ ;..............................................
L______ ________________;w
Watthour______________________ ____________ ______ ____________ ;
Weight of a major item, Total weight................... ...'........................ Weight rate, Weight per unit of power, Weight per unit of time..
___
_________ __ whr W
Work (total)........................................................................................
.W
CONVERSION EQUATIONS
Heat, Power and Work
.1 tori refrigeration Latent heat of ice 1 Btu
1 watthour
1 kilowatthour
1 kilowatt (1000 watts) 1000 mean calorie 1 1 kilogram calorie /
1 horsepower
1 boiler horsepower
Weight and Volume
/ 12,000 Btu per hour \ 200 Btu per minute
143.4 Btu per pound
778.26 ft-lb 0.293 whr 252 mean calories
2,655 ft-lb 3.413 Btu 3600 joules 860 mean calories
3,413 Btu 3.517 lb water evaporated from
and at 212 F 1.341 hp 56.88 Btu per minute 44,253 ft-lb per minute 3.969 Btu 3087 ft-lb 1.1627 whr
0.746 kw 42.42 Btu per minute 33,000 ft-lb per minute 550 ft-lb per second
( 33,475 Btu per hour L 9.808 kw
1 gal (U. S.)
1 British or Imperial gallon
1 cu ft
1 cu ft water at 60 F 1 cu ft water at 212 F 1 gal water-at 60 F 1 gal water at. 212 F
1 lb (avdp)
1 bushel1 short ton
_ / 231 cu in. - \ 0.1337 cu ft = 277.42 cu in. = ./ 7.48 gal
\ 1728 cu in. = 62.37 lb = 59.83 lb = 8.34 lb
= 7.998 lb / 16 oz \ 7000 grains
= 1.244 cu ft
= -2000 lb . .
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CHAPTER 48.: ABBREVIATIONS, SYMBOLS, STANDARDS
Pressure
1 lb per square inch
f 144 lb per square foot _ I 2.0421 in. mercury at 62 F
| 2.309 ft water at 62 F ( 27.71 in. water at 62 F
l.oz per square inch 1 atmosphere
-{ 0.1276 in. mercury at 62 F 1.732 in. water at 62 F
14.6959 lb per square inch 2117 lb per square foot 33.9 ft water at 62 F 30 in. mercury at 62 F 29.921 in. mercury at 32 F
l.in. water at 62 F 1 ft water at 62 F 1 in. mercury at 62 F
0.03609 lb per square inch 0.5774 oz per square inch 5.196 lb pet square foot
-{ 0.433 lb per square inch 62.35 lb per square foot
0.491 lb per square inch 7.84 oz per square inch 1.131 ft water at 62 F 13.58 in. water at 62 F
Metric Units
1 cm
.1 in.
'
In
,-
"
1 ft 1 sq cm
1 sq in/
1 sq m
1 sq ft
1 cu cm
1 cu in.
1 cu m.
1 cu ft
1 liter
1 kg
1 lb
1 metric ton
1 gram : ' '
1 kilometer per hour
-
1 gram per square centimeter
= 0.3937 in. = 2.540 cm = 3.281 ft = 0.3048 m = 0.155 sq in. = 6.452 sq cm = 10.76 sq ft = 0.0929 sq m = 0.06102 cu in. = 16.39 cu cm = 35.31 cu ft = 0.02831 cu m = 1000 cu cm = 0.2642 gal = 2.205 lb (avdp) = 0.4536 kg = 2205 lb (avdp) = 0.002205 lb (avdp) = 0.6214 mph
0.02905 in. mercury at 62 F 0.3944 in. water at 62 F .
1 kg per sq cm (metric atmosphere) 1 gram per cubic centimeter 1 dyne
1 joule .,
1 metric horsepower _ .
= 14.22 lb per square inch
_ / 0.03613 lb per cubic inch \ 62.43 lb per cubic foot
= 0.00007233 poundals
(10,000,000 ergs
,
- \ 0.7376 ft-lb
/ 75 kg-m per second - \ 0.986 hp (U. S.)
1 kilogram-calorie per kilogram
=1.8 Btu per pound
1 gram-calorie per square centimeter
= 3.687 Btu per square foot
1 gram-calorie per square centimeter per centimeter = 1.452 Btu per sq ft per inch
1 gram-calorie per second per -square centimeter ( 2903 Btu per hour per square
For a" temperature gradient of 1 deg C per centi- = I foot for a temperature gradient
meter. - -
( of 1 deg F per inch of thickness.
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