(Solved): The 5m5m room is heated by under floor heating systems schematically shown below. The thickne ...
The 5m×5m room is heated by under floor heating systems schematically shown below. The thickness of the floor (Z) is equal to 15cm and the volumetric energy generation rate in the floor S=S0?(1+bz), where S0?[Wm?3] is the specific energy generation rate and b [m?1] is a proportionality constant. The bottom surface of the floor is perfectly insulated and the top surface is kept at constant temperature of 298K. a) Select the general form of the energy balance equation in an appropriate coordinate system; b) Simplify the energy balance to describe the heat transfer in the floor justifying all the assumptions, and derive a differential equation and boundary conditions describing the steady state temperature distribution in the floor; c) Solve the resulting equation and sketch temperature distribution. Use the steady state temperature distribution to calculate total amount of heat transferred from the floor to the room; d) The air is flowing through the room at the flow rate of 15kgmin?1. Calculate the energy generation rate S0? necessary to keep the temperature in the room equal to 20?C. The temperature of the air outside the room is equal to 5?C. Data: Proportionality constant: b=0.5m?1 Properties of the floor. K=1.5Wmm?1,?=2000kgm?3,cp?=850Jkg?1K?1 Physical properties of air: from handbook/online data base.