Airflow through a long, 0.15-m-square air conditioning ductmaintains the outer duct surface temperature at 10°C. If thehorizontal duct is uninsulated and exposed to air at 35°C in thecrawlspace beneath a home, what is the heat gain per unit length ofthe duct? Evaluate the properties of air at 300 K. For the sides ofthe duct, use the more accurate Churchill and Chu correlations forlaminar flow on vertical plates.
What is the Rayleigh number for free convection on the outersides of the duct? 7709251
What is the free convection heat transfer coefficient on theouter sides of the duct, in W/m2·K? 4.87
What is the Rayleigh number for free convection on the top ofthe duct? 965073
What is the free convection heat transfer coefficient on the topof the duct, in W/m2·K? NEED HELP HERE
What is the free convection heat transfer coefficient on thebottom of the duct, in W/m2·K? NEED HELP HERE
What is the total heat gain to the duct per unit length, in W/m?NEED HELP HERE
I cant figure out 4,5 and 6. I swear they are correct but theonline homework won't take it.
