ENGINEERING MANUAL OF AUTOMATIC CONTROL
GENERAL ENGINEERING DATA
479
HEAT TRANSFER
Table 11. Coefficient of Heat Transfer
Conversion Multipliers.
EXAMPLE:
300 Kcal/hr•sq m•˚C x 0.205 = 61.5 Btu/hr•sq ft•˚F
VELOCITY
Table 12. Velocity Conversion Multipliers.
EXAMPLE:
950 feet per minute x 0.00508 = 4.83 meters per second
FLOW
Table 13. Flow (Gas/Air) Conversion Multipliers.
EXAMPLE:
900 cubic feet per minute x 0.4719 = 424.71 liters per second
Table 14. Flow (Liquid) Conversion Multipliers.
Desired Unit
Existing Unit
Btu
hr•sq ft•˚F
Kcal
hr•sq m•˚C
Btu/hr•sq ft•˚F — 4.88
Kcal/hr•sq m•˚C 0.205 —
EXAMPLE:
84 US gallons per min ute x 3.785 = 317.94 liter s per min ute
Desired Unit
Existing Unit
Feet
per
minute
(ft/min)
Feet per
second
(ft/s)
Meters
per
minute
(m/min)
Meters
per
second
(m/s)
Feet per
minute (ft/min)
— 0.016667 0.3048 0.00508
Feet per
second (ft/s)
60 — 18.2882 0.3048
Meters per
minute (m/min)
3.281 0.05468 — 0.016667
Meters per
second (m/s)
196.8 3.281 60 —
Desired Unit
Existing Unit
Cubic Feet per
minute (cfm)
Cubic Feet
per seconds (cfs)
Cubic Meters
per second (m
3
/s)
Liters per
second (L/s)
Cubic Feet per minute (cfm) — 0.016667 0.0004719 0.4719
Cubic Feet per second (cfs) 60 — 0.02832 28.32
Cubic meters per second (m
3
/s) 2119 35.31 — 1000
Liters per second (L/s) 2.119 0.03531 0.001 —
Desired Unit
Existing Unit
Cubic feet
per minute
(cfm)
Gallons US
per minute
(gpm)
Gallons
Imp
per minute
(gpm)
Liters
per
hour
(L/h)
Liter
per second
(L/s)
Cubic
meters per
hour
(m
3
/h)
Cubic
meters per
second
(m
3
/s)
Cubic feet per minute (cfm) — 7.482 6.23 1699.0 0.4719 1.6992 0.0004719
Gallons US per minute
(gpm)
0.13368 — 0.8327 227.1 0.06309 0.2271 0.0000631
Gallons Imp per minute
(gpm)
0.1605 1.20095 — 272.8 0.07577 0.27274 0.0000758
Liters per hour (L/h) 0.0005886 0.0044 0.00367 — 0.002778 0.001 0.0000003
Liters per second (L/s) 2.119 15.85 13.20 3 600 — 3.6 0.001
Cubic meters per hour
(m
3
/h)
0.5886 4.4028 3.666 1 000 0.2778 — 0.0002778
Cubic meters per second
(m
3
/s)
2118.9 15850 13 198.2 3 600 000 1 000 3599.7 —
1 gpm water at 20F ∆T = 10 000 Btuh