Please solve it complete in 30 minute Consider an apartment in a tower block as a cube of side L = 7.77 m. Since this apartment is designed to be rentedby a student, it has no windows. The floor and ceiling are perfectly insulated, but the wall is made of concrete ofthickness d = 15.0 cm. The thermal conductivity of the concrete is k = 0.610 Wm¯'K-.Part 1)The outside temperature is stable at Toutconditioner if the occupant wants to keep the inside temperature stable at Tin= 37.2°C. What is the heat load (rate of heat transfer) on the air18.0°C?P =kWPart 2)A layer of insulation of thickness dins= 43.7 mm and thermal conductivity kins = 0.0254 Wm¬K¯ is added tothe walls. What is the heat load now?P =kWPart 3)The occupant complains that the apartment is dank and dark, so the landlord is forced to install windows and a door.These are constructed, but then drafts from the gaps around the windows and doors allow the air in the apartment tochange every 2 hours. How much additional heat load does changing this air add. The specific heat of air isc = 1.0 kJkgK and the density of air is p = 1.0kgm¯³.AP =kW

Given data The Room can be considered as a cube with dimensions 7.77 mThe thickness of the wall = d…

Consider an apartment in a tower block as a cube of side L = 7.77 m. Since this apartment is designed to be rented by a student, it has no windows. The floor and ceiling are perfectly insulated, but the wall is made of concrete of thickness d = 15.0 cm. The thermal conductivity of the concrete is k = 0.610 Wm¯'K¯'. Part 1) The outside temperature is stable at Tout conditioner if the occupant wants to keep the inside temperature stable at Tin 37.2°C. What is the heat load (rate of heat transfer) on the air 18.0°C? %3D P = kW Part 2) A layer of insulation of thickness dins = 43.7 mm and thermal conductivity kins -1 = 0.0254 Wm¯'K¯ is added to the walls. What is the heat load now? P = kW Part 3) The occupant complains that the apartment is dank and dark, so the landlord is forced to install windows and a door. These are constructed, but then drafts from the gaps around the windows and doors allow the air in the apartment to change every 2 hours. How much additional heat load does changing this air add. The specific heat of air is c = 1.0 kJkg"K and the density of air is p = 1.0kgm -3 AP = kW

Consider an apartment in a tower block as a cube of side L = 7.77 m. Since this apartment is designed to be rented by a student, it has no windows. The floor and ceiling are perfectly insulated, but the wall is made of concrete of thickness d = 15.0 cm. The thermal conductivity of the concrete is k = 0.610 Wm¯'K¯'. Part 1) The outside temperature is stable at Tout conditioner if the occupant wants to keep the inside temperature stable at Tin 37.2°C. What is the heat load (rate of heat transfer) on the air 18.0°C? %3D P = kW Part 2) A layer of insulation of thickness dins = 43.7 mm and thermal conductivity kins -1 = 0.0254 Wm¯'K¯ is added to the walls. What is the heat load now? P = kW Part 3) The occupant complains that the apartment is dank and dark, so the landlord is forced to install windows and a door. These are constructed, but then drafts from the gaps around the windows and doors allow the air in the apartment to change every 2 hours. How much additional heat load does changing this air add. The specific heat of air is c = 1.0 kJkg"K and the density of air is p = 1.0kgm -3 AP = kW

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.26P

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As a designer working for a major electric appliance manufacturer, you are required to estimate the amount of fiberglass insulation packing (k = 0.035 W/m K) that is needed for a kitchen oven shown in the figure below. The fiberglass layer is to be sandwiched between a 2-mm-thick aluminum cladding plate on the outside and a 5-mm-thick stainless steel plate on the inside that forms the core of the oven. The insulation thickness is such that the outside cladding temperature does not exceed 40C when the temperature at the inside surface of the oven is 300C. Also, the air temperature in the kitchen varies from 15Cto33C, and the average heat transfer coefficient between the outer surface of the oven and air is estimated to be 12.0W/m2K. Determine the thickness of the fiberglass insulation that is required for these conditions. What would be the outer surface temperature when the inside surface of the oven is at 475C?
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