A large bare duct having a diameter of 25cm runs horizontally across a factory area having environmental conditions of 20.C and 1 atm. The length of the duct is 100 m. Inside the duct a low pressure...

Extracted text: A large bare duct having a diameter of 25cm runs horizontally across a factory area having environmental conditions of 20.C and 1 atm. The length of the duct is 100 m. Inside the duct a low pressure steam flow maintains the duct wall temperature constant at 120.C. Calculate the total heat lost by convection from the duct to the room