Hi all, I have a unique problem that I need help with
A company's curing oven's exposed surface temperature is measured at 80°c when the surrounding air is 23°c. You think it should be insulated and wager to pay for the cost of this yourself if you can keep the savings incurred. Is this a smart move? the oven is 3.7m long and 2.4m diameter. The plant operates 16 hours/day 365 days/year. The insulation to be used is fiberglass (Kins = 0.08 W/m/°c, assumed constant) which costs $2.5/m2 per cm thickness plus $21.5/m2 for labour regardless of tthickness. Convective heat transfer coefficient on the outer surfaced is estimated to be h0= 20W/m2/K. The oven uses natural gas, whose unit cost is £7.1/GJ input and the oven's efficiency is 80%.
Ignoring radiation heat loss from the outer surface, determine
A) how much money you will make out of this venture, by installing one inch (1 inch = 2.54 cm) of insulation, if any, and
B) the thickness of insulation (to nearest inches) that will maximise your earnings
Any input would be greatly appreciated as I'm well and truly stuck