Thermodynamics HW Solutions 265

Thermodynamics HW Solutions 265 - Chapter 3 Steady Heat...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 3 Steady Heat Conduction 3-155 Hot water is flowing through a 3-m section of a cast iron pipe. The pipe is exposed to cold air and surfaces in the basement, and it experiences a 3°C-temperature drop. The combined convection and radiation heat transfer coefficient at the outer surface of the pipe is to be determined. Assumptions 1 Heat transfer is steady since there is no indication of any significant change with time. 2 Heat transfer is one-dimensional since there is thermal symmetry about the centerline and no significant variation in the axial direction. 3 Thermal properties are constant. Properties The thermal conductivity of cast iron is given to be k = 52 W/m °C. Analysis Using water properties at room temperature, the mass flow rate of water and rate of heat transfer from the water are determined to be & & (/ & & (. ) ( ) mV V A Qm CT cc p == = = ° ° ρρ π 1000 4 106 70 67 kg / m )(1.5 m / s)
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.
Ask a homework question - tutors are online