Problem: A horizontal steel pipe of diameter 50 mm is maintained at at a temperature of 500C in a large room where air and room temperature are at 25oC. The heat is lost by free convection and radiation. The surface emissivity of steel may be taken as 0.8. An estimate for the heat transfer coefficient for free convection with this geometry and air is 6.5 W/m2oC.
Part I: Calculate the total heat lost by pipe per unit length.
Please show the work for the calculation so I can understand what I'm doing in above problem. Thanks!