Question: A building with an internal volume of 400 m3 is to be heated by a 30-kW electric resistance heater placed in the duct inside the

A building with an internal volume of 400 m3 is to be heated by a 30-kW electric resistance heater placed in the duct inside the building. Initially, the air in the building is at 14°C, and the local atmospheric pressure is 95 kPa. The building is losing heat to the surroundings at a steady rate of 450 kJ/min. Air is forced to flow through the duct and the heater steadily by a 250-W fan, and it experiences a temperature rise of 5°C each time it passes through the duct, which may be assumed to be adiabatic.
(a) How long will it take for the air inside the building to reach an average temperature of 24°C?
(b) Determine the average mass flow rate of air through the duct.

A building with an internal volume of 400 m3

450 kJ/min V-400 m3 P= 95 kPa 14C 24C Im 250 W

Step by Step Solution

3.34 Rating (169 Votes )

There are 3 Steps involved in it

1 Expert Approved Answer
Step: 1 Unlock

A building is to be heated by a 30kW electric resistance heater placed in a duct inside The time it ... View full answer

blur-text-image
Question Has Been Solved by an Expert!

Get step-by-step solutions from verified subject matter experts

Step: 2 Unlock
Step: 3 Unlock

Document Format (1 attachment)

Word file Icon

E-ME-T (1766).docx

120 KBs Word File

Students Have Also Explored These Related Mechanical Engineering Questions!