Honeywell AUTOMATIC CONTROL SI Edition, Engineering Manual

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ENGINEERING MANUAL OF AUTOMATIC CONTROL
GENERAL ENGINEERING DATA
468
VOLUME
Table 7. Volume Conversion Multipliers.
EXAMPLE:
64 gallons (US) x 3.7854 = 242.27 liters
MASS PER UNIT VOLUME OF WATER
62.383 lb/ft 3 or 8.343 lb/gal
0.999 kg/l or 9.99 g/cm
3
SPECIFIC HEAT
Specific heat of water = 1
Specific heat of steam (water vapor) = 0.49
Specific heat of air = 0.24
The specific heat of water is the reference for all other substances
and means that one Btu will change the temperature of one pound
of water one degree Fahrenheit. If a substance has a specific heat
of 0.25, then 1/4 Btu will change the temperature of the substance
one degree Fahrenheit or one Btu will change the temperature of
that substance four degrees Fahrenheit.
Similarly, 4.7 kJ will change the temperature of one kilogram
of water one kelvin. If a substance has a specific heat of 0.25,
then 4.7 kJ will change the temperature of that substance four
kelvins.
EXAMPLE:
1 gpm water at 20F
∆
T = 10 000 Btuh
1 L/s water at 10 kelvins = 1692 kJ per hour
TEMPERATURE
Most temperature conversions will be between Fahrenheit
and Celsius (Centigrade) scales. These cannot be done with a
simple multiplier. The formulas are:
Temperature in degrees F = 9/5 x degrees C + 32.
Temperature in degrees C = 5/9 x (degrees F – 32).
Since Fahrenheit and Celsius scales coincide at –40 the
following alternate formulas may be used:
Temperature in degrees F = 9/5 x (degrees C + 40) – 40.
Temperature in degrees C = 5/9 x (degrees F + 40) – 40.
NOTE: A temperature range or span does not require
the factors to adjust the zero reference of the
temperature scales. A range or span is denoted
as Degrees Fahrenheit or Degrees Kelvin (K)
and converted as follows:
Degrees F = 9/5 x degrees K
Degrees K = 5/9 x degrees F
Absolute zero is noted in degrees Rankine (R) or Kelvin.
The approximate conversions are:
Degrees R = degrees F + 460.
Degrees K = degrees C + 273.
Desired Unit
Existing Unit
Cubic
inches
(in. 3)
Cubic feet
(ft 3)
Cubic
centimeters
(cm 3)
Gallons,
US
(US gal)
Gallons,
Imp
(Imp gal)
Liters
(L)
Ounces,
fluid
(oz fluid)
Quarts,
liquid
(qt liquid
Cubic
meters
(m 3)
Cubic inches
(in.
3
)
— 0.0005787 16.387 0.004329 0.003605 0.016387 0.5541 0.0173 0.0000164
Cubic feet (ft
3
) 1728 — 2832 7.481 6.229 28.32 957.5 29.92 0.002832
Cubic centimeters
(cm
3
)
0.06102 0.0000353 — 0.0002642 0.00022 0.001 0.0338 0.01057 0.000001
Gallons, US
(US gal) 231 0.13368 3785.4 — 0.8327 3.7854 128 4 0.003785
Gallons, Imp
(Imp gal) 277.42 0.16054 4546 1.2009 — 4.546 153.7 4.803 0.004546
Liters (L) 61.024 0.03531 1 000 0.2642 0.22 — 33.818 1.0568 0.001
Ounces, fluid
(oz fluid) 1.805 0.001044 29.58 0.007813 0.0065 0.02957 — 0.03125 0.0000296
Quarts,
(qt liquid) 57.75 0.03342 946.4 0.25 0.2082 0.9463 32 — 0.0009463
Cubic meters
(m
3
)
6 1024 35.31 1 000 000 264.2 220 1 000 33 814 1056.7 —