Question

Compute the steady-state heat transfer rate per square meter (W/m2)through a flat built-up roof-ceiling combination as follows: asphalt roll roofing 10 mm built-up roofing 50 mm preformed deck insulation 20 cm lightweight concrete slab 90 mm non reflective air space 20 mm lightweight aggregate on metal lath. Assume still air inside and outside summer conditions. Indoor and outdoor temperatures are 24 and 47 oC, respectiely.

Answer 1

Steady state heat transfer rate insulation = 20 cm, roof reeling = 10 mm, T_i = 24 degree C T_o = 47 degree C q degree = pi/4 D times l times (Delta T) q degree = 722.56 w