A food cold storage room is to be constructed of an inner layer of 19.1 mm of pine wood, a middle layer of cork board, and an outer layer of 50.8 mm of concrete. The inside wall surface temperature is -17.8°C and the outside surface temperature is 29.4 °C at the outer concrete surface. The mean conductivities are for pine, 0.151; cork, 0.0433; and concrete, 0.762 W/m·K. The total inside surface area of the room to use in the calculation is approximately 39 m2 (neglecting corner and end effects). What thickness of cork board is needed to keep the heat loss to 586 W?

There is a 1.20-cm-thick stagnant air pocket. A) What thickness of cork would have the same R-factor as the stagnant air pocket? The thermal conductivity of air is 0.0230 W/m·K and of cork is 0.0460 W/m·K.in cm  B) What thickness of tin would be required for the same R-factor as a 1.20-cm-thick stagnant air pocket? The thermal conductivity of air is 0.0230 W/m·K and of tin is 66.8 W/m·K . in m i asked how to do this but got the wrong soloution

A 1-in Sch 40 stainless steel pipe with a thermal conductivity of 45 W/m-K can move 1,000 kg of saturated steam per hour at 150 °C. Refractory material 0.25 inches thick with a thermal conductivity of 0.025 W/m-K insulates the pipe. At a temperature of 25 °C, the pipe is exposed to the outside air. There is a 1135 W/m2 internal heat transfer coefficient.40 W/m2-K is the outside heat transfer coefficient, whereas -K. Suppose that only the radial direction is involved in steady-state heat transfer and that radiation effects are negligible. ✓ Determine how much heat is being lost through these pipes to the environment.a. 399.1 W/mb. 1525.0 W/mc.  618.4 W/md. 1128.7 W/me. none of the above √  How about the insulated pipe's surface temperature?a. 118.5 °Cb. None of the abovec. 101.5 °Cd. 216.3 °Ce. 292.2 °C

1) A wall section composed from the outside to inside, of concrete brick 100mm thick, an air space of 50mm, two layers of fiberglass insulation 38mm thick, concrete block 150mm thick and air space of 19mm and a gypsum board of 13mm. The exterior conditions are -20C and RH=90% while the interior conditions are 23C and RH=40%. The surface temperature from the outside to inside are shown in the figure. The permeances are: Still Air: µ = 175 ng/pa.s.m Fiber glass: M=2560 ng/pa.s.m? Concrete block: M= 200 ng/pa.s.m? Gypsum board: M= 2000 ng/pa.s.m? Concrete brick: µ = 4.55 ng/pa.s.m Determine if there is a risk of condensation, and if there is, what is the condensation rate? What would happen if a vapor barrier (M=0.2 ng/pa.s.m²) was installed on the warm side of the insulation (Surface 4). 21с 19C 16 С 12C -10 -15C -18C -19C Gyp Air Concrete Fiber Fiber Air Concrete Outdoor Indoor sum block Glass Glass brick 230 19 50 mm -20C 13 150 mm 38 mm | 38 mm 100 mm RH=90% RH=40% mm mm Surf. 1 Surf.…

Calculate the heat loss through a 100-ft² wall with an inside temperature of 65°F and an outside temperature of 35°F. Assume the exterior wall is composed of 2- in. of material having a 'k' factor of 0.80, and 2-in. of insulation having a conductance of 0.16. RTotal = 8.75 & Q = 342-Btu/hr RTotal = 9.2 & Q = 399-Btu/hr RTotal = 8.75 & Q = 399-Btu/hr RTotal = 9.2 & Q = 342-Btu/hr Hide hint for Question 3 Utilize the (RTotal = 1/C + x1/k1) equation.

The thermal conductivities of human tissues vary greatly. “Fat” and “skin” have conductivities of approximately 0.200 W /m 0K and 0.0200 W /m 0K, respectively, while other “tissues” inside the body have conductivities of approximately 0.500 W /m 0 Assume that between the core region of the body and the skin surface lies a “skin” layer of 1.00mm, a “fat” layer of 0.500 cm., and 3.20 cm. layer of other “tissues”. A)Find the R-factor for each of these three layers, and the R-factor for all layers taken together

An industrial cold room has four 200 mm thick walls made of concrete. The walls are insulated on the outside with a layer of foam 60 mm thick. Cladding with a thickness of 15 mm protects the foam on the outside from the elements. The composite wall surface temperatures are –3 °C on the inside and 18 °C on the outside of the room respectively. The thermal conductivities of concrete, foam and cladding are 0.75, 0.35 and 0.5 W/m K respectively.   Assuming perfect thermal contact between the layers of the composite walls, draw the typical temperature distribution across the layers and determine the heat energy gained per hour through all 4 walls of the room with a total surface area of 20 m2. What does this heat energy represent in terms of the refrigeration system of the cold room?