. Electrically heated automobile rear window defoggers utilize a thin transparent film-type heating element attached to the inner surface of the window. As shown below, the window glass is 4 mm thick and the inner surface of the window is maintained at 15 °C (Tinner). The total surface area of the window is 1 m². Both sides of the window experience convective heat transfer with the properties shown below. The thermal conductivity of the glass is 1.4 W/m-K. Assume that the thickness of the heating film is negligible. a) Construct the thermal circuit representing the steady state heat transfer for the system. Label all nodes, resistances and relevant terms. b) Determine the (electrical) power (in Watts) to maintain the conditions given. 4 mm A=1m² Tinner 11 Too2 = -10 °C h = 65 W/m²-K Outer Window Glass Heater T∞01 = 25 °C h = 10 W/m²-K Inner

A-For a general office room, the exposed wall (with a window, outside winter type) construction is 19 mm plaster outside (cement and sand) and 20 cm brick (building). The area of the window is 50% of the exposed wall. Calculate the heating load required for the office caused by the wall and window. Take Tout-5 °C and Tin-25 °C, exposed wall height=3 m and width=5 m, Inside and outside still air thermal resistance fi= 9.37 W/m²°C and fo= 34.1 W/m2 °C respectively. (6 marks)

Please solve asap, Will provide helpful ratings for complete solution. Thank u A double-glazed window is constructed such that it has 5 mm thick glass as the inside layer, 4 mm layer of gas, and finally 5 mm thick glass as the outer layer. Which have thermal conductivies of 0.7, 2.120, and 5.9 W m-1 K-1, respectively. Calculate the heat loss per unit area, Wm-2 through the glass if the inside temperature of the glass is 11.09 °C and the outside temperature is 6.47 °C Report your answer to 2 decimal places.

1. A composite furnace wall is made up of a 12-in. lining of magnesite refractory brick, a 5-in.thickness of 85% magnesia, and a steel casing 0.10-in. thick. Flue gas temperature is 2200 F andthe boiler room is at 80 F. Gas side film coefficient is 15 Btu/hr-sq.ft-F and air side is 4.0.Determine:a. The thermal current Q/Ab. Interface temperaturesc. Effect on thermal current and inside refractory wall temperature if the magnesia insulation weredoubled.

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A square silicon chip 7 mm x 7 mm in size and 0.5-mm thick is mounted on a plastic substrate as shown in the sketch below. The top surface of the chip is cooled by a synthetic liquid flowing over it. Electronic circuits on the bottom of the chip generate heat at a rate of 5 W that must be transferred through the chip. Estimate the steady-state between the front and back surfaces of the temperature difference chip. The thermal conductivity of silicon is W 150 mK Silicon chip Synthetic liquid Substrate

A composite wall consists of 2” corkboard (inner), 6” concrete and 3” wood (outer). The thermal conductivity of the materials are 0.025, 0.8 and 0.065 Btu/hr-ft-oF. The temperature of the inner surface of the wall is 40oF while the outer surface of the composite wall is 78oF. What is the temperature in oF between cork and concrete and between concrete and wood?

Determine the optimum thickness from an economic point of view, of insulation for a steam pipe 100 mm dia. at 465°C. The insulation conductivity is 1.55 x 10 kW/mK, the natural convection coefficient -4 on the insulation outer surface is 0.0112 kW/m2K, the insulation cost is £70/m³ plus a fixed charge of 160p. per metre run of pipe and the cost is to be spread over 5 veres. The oil fuel, of density 900 kg/m³, costs 1.lp. per litre and is used to raise steam in a boiler of 90% efficiency. The fuel calorific value is 41,000 kJ/Kg and the air temperature surrounding the insulation is 27°c.

A camera used for monitoring marine life is placed in water where T.. -5°C and the convection heat transfer coefficient h=1420 W/m²K. The camera is operating, but its battery is experiencing thermal runaway, causing the camera to become very hot, and there is volumetric heat generation, qe inside it. There is no heat generation within the waterproof, protective enclosure surrounding it. 00:08 The camera is already compromised; however, its owner hopes to save the protective case. Each interface (between layers A and B and between layers B and C) must not exceed a temperature of 185°C, or these plastic, protective layers will begin to melt. Approximate the camera and its casing as a composite, rectangular object with flat surfaces. The device's total thickness, L=LA + 2LB +Lc, is much smaller than its area (into the page); therefore, 1-D conduction can be approximated through the layers. On the left surface of layer A, the temperature is measured to be T₁ = 8.0°C, and the temperature on…

The Diamond Ring Solution. The processing chip on the computer that controls the navigation equipment on your spacecraft is overheating. Unless you fix the problem, the chip will be damaged and the navigation system will shut down. You open the panel and find that the small copper disk that was supposed to bridge the gap between the smooth top of the chip and the cooling plate is missing, leaving a 2.0 mm gap between them. In this configuration, the heat cannot escape the chip at the required rate. You notice by the thin smudge of thermal grease (a highly thermally conductive material used to promote good thermal contact between surfaces) that the missing copper disk was 2.0 mm thick and had a diameter of 1.0 cm. You know that the chip is designed to run below 70 °C, and the copper cooling plate is held at a constant 5.0 °C. (a) What was the rate of heat flow from the chip to the copper plate when the original copper disk was in place and the chip was at its maximum operating…