A wall is 20 ft (6.1 m) wide and 8 ft (2.4 m) high and has an overall heat-transfer coefficient of
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- An office space of 14 ft x114 ft x12 ft height. The heat loss through roof is (5131.3 Btuh) if Tb.l.=70 F, To= 5 F , and Uwall=0.35 Btu/hr.ft2.F * O True O Falsearrow_forward2. Calculate the heat loss for the structure described below. Use the indoor design setpoint of 70°F. ● . . . ● ● Hint: Utilize the Q=U*A*(ti-to) & Q = U'*P*(ti-to). Make sure to reference the following tables and examples to help assist you solve this problem; Table 5-5a, Table 5-8, Table 5-4a, Example 5-3, Eq. 5-23, and Fig 5-8. Given: i. Location: Des Moines, IA @ 99% winter OAT ii. Walls: Table 5.7, Construction 2 iii. Floor: Concrete slab with 2-ft, R-5.4, vertical edge insulation iv. Windows: Double-Insulating Glass; 1/4-in. air space; e = 0.6 on surface 2, 3x4-ft, double hung, reinforced vinyl frame; three on each side v. vi. Roof-Ceiling: Same as Example 5.3, height of 8-ft vii. House Plan: Single story, 36-ft x 64-ft Doors: Wood, 1-3/4-in. panel doors with metal storm doors, three each, 3x6.75-ft Qwindows = Qdoors= Qwalls = Qroof/ceiling= Qfloor = QTOTAL = Btu/(hroft²0F) Btu/h Heat Loss Btu/h Heat Loss Btu/h Heat Loss Btu/h Heat Loss Btu/h Heat Lossarrow_forwardThe interior-wall temperature of an annealing oven constructed of firebrick (Missouri) is2552°F, and the exterior-wall temperature is 392°F. If the heat loss is 3600 Btu/(hr)(sq ft),determine the thickness of the wall, in inches. (answer 5.67”)arrow_forward
- The thermal conductivities of wood is kwood = 0.1W/(m°C)and air is kair = 0.0234W/(m°C). Part A If the temperature of the room is 20°C and outside is 10°C, find the rate of heat flow for a wall of wood with area = 10 m² and thickness of 5cm. O 60 W O 304 W O 34 W O 200 W O 100 W Submit Request Answer Part B The wall of wood with thickness of 5cm is now replaced with two layers of wood and a gap of air between the wood. Each layer of wood has a 2.5cm thickness and the gap is 1cm. The rate of heat flow will, decreases. increases. stay the same. Submit Request Answer Part C The temperature in the air gap will be, O 20°C, between 10°C and 20°C, O 10°C,arrow_forwardAnswer this ASAP The diameter of the tube is 25 mm. The specific heat of water is 4.18 kJ/kg.°C. The overall heat transfer coefficient is 0.7 kW/m².°C. 1. Schematic of temperature distribution 2.ΔTLMTD 3.Actual heat transfer rate 4.Cmin 5.Maximum heat transfer ratearrow_forwardQuestion 4: Water flows on the inside of a steel pipe with an ID of 2.5 cm. The wall thickness is 2 mm, and the convection coefficient on the inside is 500 W/m2◦C. The convection coefficient on the outside is 12 W/m2 ◦C. Calculate the overall heat-transfer coefficient.arrow_forward
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