Calculates the Temperature Change of Water Flowing in a Pipe (Reference: 2009 ASHRAE HoF, Chapter 4, Equation 48, (pg 4.21))
This calculator estimates the temperature drop (or rise) of water flowing in a pipe.
(Input information may generally be be obtained from design documents or field measurements)
- Line 1. Enter the temperature of the water entering the pipe
- Line 2. Enter the ambient temperature (temperature of the air surrounding the pipe)
- Line 3. Enter the wind speed of the ambient air in miles per hour
- Line 4. Enter the flow rate of the water carried by the pipe in gallons per minute.
Note: Calculator does not screen for reasonable flow velocities, Hydronic piping is normally sized for flow velocities between 5 and 12 feet/sec
- Line 5. Enter the length of the piping run in feet
- Line 6. Select the nominal pipe size in inches
- Line 7. Select the nominal thickness of insulation in inches
- Line 8. Select an insulation material.
Note: Calculator does not screen for material temperature limitations.
- Line 9. Select thermal emittance of the outer jacket material.
Note: NA = Insulation Size Not Available. Some sizes and thicknesses may not be commercially available.
- One dimensional, steady state heat transfer
- U-factor constant at average conditions
- Thermal resistance of film at inner pipe surface neglected
- Thermal conductivity based on ASTM Specification Values. Refer to the introductory notes for further clarifications.