Engineering Manual o.. - HVAC.Amickracing

GENERAL ENGINEERING DATAHEAT TRANSFERTable 9. Coefficient of Heat TransferConversion Multipliers.Desired UnitBtuKcalExisting Unit hr•sq ft•˚F hr•sq m•˚CBtu/hr•sq ft•˚F — 4.88Kcal/hr•sq m•˚C 0.205 —EXAMPLE:300 Kcal/hr•sq m•°C x 0.205 = 61.5 Btu/hr•sq ft•°FVELOCITYTable 10. Velocity Conversion Multipliers.Desired UnitExisting UnitFeet perminute (ft/min)Feet persecond (ft/s)Meters perminute (m/min)Meters persecond (m/s)Feetperminute(ft/min)Feet persecond(ft/s)Metersperminute(m/min)Meterspersecond(m/s)— 0.016667 0.3048 0.0050860 — 18.2882 0.30483.281 0.05468 — 0.016667196.8 3.281 60 —EXAMPLE:950 feet per minute x 0.00508 = 4.83 meters per secondFLOWEXAMPLE:900 cubic feet per minute x 0.4719 = 424.71 liters per secondEXAMPLE:84 US gallons per minute x 3.785 = 317.94 liters per minuteTable 11. Flow (Gas/Air) Conversion Multipliers.Desired UnitExisting UnitCubic Feet perminute (cfm)Cubic Feetper seconds (cfs)Cubic Metersper second (m3/s)Liters persecond (L/s)Cubic Feet per minute (cfm) — 0.016667 0.0004719 0.4719Cubic Feet per second (cfs) 60 — 0.02832 28.32Cubic meters per second (m3/s) 2119 35.31 — 1000Liters per second (L/s) 2.119 0.03531 0.001 —Table 12. Flow (Liquid) Conversion Multipliers.GallonsImpper minute(gpm)Desired UnitCubicmeters perhour(m 3 /h)Cubicmeters persecond(m 3 /s)Existing UnitCubic feetper minute(cfm)Gallons USper minute(gpm)Litersper hour(L/h)Literper second(L/s)Cubic feet per minute (cfm) — 7.482 6.23 1699.0 0.4719 1.6992 0.0004719Gallons US per minute(gpm)Gallons Imp per minute(gpm)0.13368 — 0.8327 227.1 0.06309 0.2271 0.00006310.1605 1.20095 — 272.8 0.07577 0.27274 0.0000758Liters per hour (L/h) 0.0005886 0.0044 0.00367 — 0.002778 0.001 0.0000003Liters per second (L/s) 2.119 15.85 13.20 3 600 — 3.6 0.001Cubic meters per hour(m3/h)0.5886 4.4028 3.666 1 000 0.2778 — 0.0002778Cubic meters per second 2118.9 15850 13 198.2 3 600 000 1 000 3599.7 —(m3/s)1 gpm water at 20F ∆T = 10 000 Btuh470ENGINEERING MANUAL OF AUTOMATIC CONTROL