- 3 A 10 Feet High 12 Feet Wide Wall Has A 6 Feet Wide And 4 Feet High Double Glass Window In It The Details Of Wall An 1 (62.75 KiB) Viewed 23 times
3. A 10 feet high, 12 feet wide wall has a 6 feet wide and 4 feet high double glass window in it. The details of wall and window construction are shown in the following figure. TOP VIEW Direction of heat transfer Inside (h), T-72 F WASTARA outside (hal. T 104 F -6 ft Wall 12 ft. FRONT VIEW Window T 4 ft. 10 ft The wall structure is composite made up of 8-in thick concrete blocks (material 2 in picture) having an aggregate density between 126-136 lb/ft'. The brick wall is covered from inside and outside with 2-in thick cement mortar (materials 1 & 3 in the picture). The window (material 4 in picture) is double glazing type without coating with % in air space between glasses. The frame is operable made up of Aluminum with thermal break. Assume wall emissivity (e) to be 0.9. (Hint: Use average conductance values where range is given) (a) Draw the thermal circuit for heat transfer through the wall-window combination showing all resistances. (b) Compute the combined heat transfer coefficient of the wall and the window. (c) Determine the overall heat transfer rate through this wall-window combination assuming summer conditions when the outside temperature is 104 F while the inside is maintained at 72 F. Neglect transmitted radiation from the glass window. LD