2. A steel plate of k=50W/mK and thickness 10cm passes a heat flux by conduction of 25kw/m2. If the temperature of hot surface of plate is 100C, then what is the temperature of the cooler side of plate?
Q: Consider a solid sphere of radius r=50 cm. The heat is generated steadily inside the sphere at a…
A: Given Data r=50 qg=1500 wm3 K=10 wm.K T∞=10oC h=125 Wm2K The temperature of the center of sphere,…
Q: Consider a solid sphere of radius r=50 cm. The heat is generated steadily inside the sphere at a…
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Q: Calculate the heat transfer in kJ per hour through a solid brick wall 8 cm, 3 m high and 225 mm…
A: Given: The outer surface temperature is Tc=5°C. The inner surface temperature is Th=17°C. The…
Q: 1. A flat plate is supplied with a constant heat flux of 100 [W/m²] from bottom. The plate has 0.5m2…
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Q: Calculate the heat transfer in kj per hour through a solid brick wall 8 cm, 3 m high and 220 mm…
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Q: An aluminum fin is attached to a transistor that generates heat at the rate of 300 W. The fin has a…
A: Given, Heat, Q=300WTotal surface area, A=9.0cm2Surronding temperature, To=27°C=300KContact area,…
Q: 1. a) A furnace wall is composed of 220 mm of fire brick, 150 mm of common brick, 50 mm of 85%…
A: Conduction is that mode of heat transfer where heat flows from higher temperature to lower…
Q: The 8-mm-thick bottom of a 220-mm-diameter pan may be made from aluminum (k = 240 W/m · K) or copper…
A: Given data: The thickness of pan, L = 8 mm. The diameter of the pan, d = 220 mm. The thermal…
Q: A steel pipe having an inside diameter of 1.68 cm and a wall thickness of 0.391 cm is subjected to…
A: Answer: (1) The heat flux based on the inside surface area of the pipe is 427.6 kW/m2. (2) The heat…
Q: The 5-mm-thick bottom of a 200-mm-diameter pan may be made from aluminum (k 240 W/m K) or copper (k…
A: Given data The 5-mm-thick bottom of a 200-mm-diameter aluminum (k = 240 W/m K) copper (k = 390…
Q: A cylindrical tube with inner and outer radius are 10 mm and 20 mm respectively and the temperature…
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Q: Consider a solid sphere of radius r=50 cm. The heat is generated steadily inside the sphere at a…
A: Given Data⇒ Radius of the solid sphere (r)=50 cm Heat generation rate is q=15000Wm3 Conductivity of…
Q: The ratio of heat flow Q/Q2 from two walls of having same thickness their thermal conductivities as…
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Q: A stainless steel alloy has cylindrical shape (k = 25 W/m.oC), diameter is 10 cm and 25 cm long,…
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Q: A 0.025-mm-diameter stainless steel wire having k = 16W / m . °C is connected to two electrodes. The…
A: Given data: It is assumed that the wire is divided into two parts and the section of the separation…
Q: A 6-in. polished copper sphere is heated electrically to maintain a surface temperature of 280 °F.…
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Q: A long pipe carries hot water and loses heat by convection to the surrounding air at Too=16 °C and…
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Q: A plane furnace surface at 150°C covered with 1-cm-thick insulation is exposed to air at 30°C, and…
A:
Q: A square plate heater (15 cm by 15 cm) is inserted between two slabs. Slab A is 2 cm thick (k-50…
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Q: A masonry brick wall (k = 0.60 W/(m K) and a = 5 x 10-7 m²/s) of 150 mm thickness and originally at…
A:
Q: Q) One side of a plane wall is maintained at 100 degrees *C while the other side is exposed to a…
A: The solution is given below
Q: b. A slab of stone of area (3600 + R) cm² and thickness 10 cm is exposed on the lower surface to…
A: Draw diagram of slab for better understanding
Q: The rate of heat flow through a hallow sphere of inner radius 0.25 m and outer radius 0.35m, whose…
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Q: Example 4.2 Two rectangles 50 by 50 cm are placed perpendicularly with a common edge. Surface one…
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Q: Example 4: A wall has the following specifications as shown in figure below: Height = 3 m. Width =…
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Q: The wall of a rectangular chemical tank consists of two layers- inner layer with 15 cm of copper (k…
A: Given, Lc = 15 cm kc = 385 W/m k Li = 10 cm ki = 60 W/m k ka = 0.17 W/m k
Q: Q5 A) A power transistor has a temperature on its face exposed to environment of 80 °C, its…
A:
Q: A plane wall has a thermal conductivity of 1.15 W/mK. If the inner surface is at 1100°C and the…
A: As per given question Thermal conductivity =1.15 w/mk Inner surfaces temp. =1100°c Outer temp.=350
Q: A furnace wall comprises three layers of thickness 250 mm, 100 mm, and 150 mm with thermal…
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Q: 3 cm thick has a constant temperature of 400 ° C while the temperature of the other surface is kept…
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Q: Consider a permanent one-dimensional heat conduction on a flat wall of length L = 0.4 m and constant…
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Q: The front window of an automobile has a thickness of 4 mm and is defrosted by the passage of a…
A: Given: The thickness of the window, x = 4 mm The thermal conductivity of glass window, k = 0.78…
Q: A copper bar (2.00 cm by 2.00 cm and 10.0 cm long) is welded end to end to a brass bar of the same…
A: Heat Transfer (cl/area) = Ts-TiLKc+LKb = Ts - TfLKc = T6 - TiLKb Tf = temperature at the interface…
Q: The rate of heat generation per unit volume in a plane wall of thickness 30 mm can be modeled as:…
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Q: A plane wall 20 cm thick with uniform internal heat generation of 200 kW/m3 is exposed to a…
A: Given:Temperature of surrounding,T∞==50οCHeat transfer coefficient,h=400Wm2οCLet the Wall…
Q: A slab of stone of area (3600 + R) cm² and thickness 10 cm is exposed on the lower surface to steam…
A: The area of the slab is given by, The temperature of the steam is given by, The specific latent…
Q: 2. A refrigerated cold room wall has a thickness of 100mm and a thermal conductivity 0.14 W/m-K. The…
A:
Q: 2. A steel plate of k=50W/mK and thickness 10cm passes a heat flux by conduction of 25kW/m2. If the…
A:
Q: the composite wall of a refrigerator has a thermal conductivity of 0.05 W/m-K and a wall thickness…
A: Given: kwall = 0.05 W/m-K b = 50 mm To = 25 C° ho = 10 W/m²K hi = 5 W/m²K Ti = 4 °C
Q: A wall with a thermal conductivity of 0.50W/m·K is maintained at 40.0°C. The heat transfer through…
A: The temperature at the outside surface is 36.67 ℃.
Q: A large stainless-steel plate (k = 10 W/m.°C) has a thickness of 2 cm. Due to the electricity…
A:
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- 3.17 A 1.4-kg aluminum household iron has a 500-W heating element. The surface area is . The ambient temperature is 21°C, and the surface heat transfer coefficient is . How long after the iron is plugged in does its temperature reach 104°C?Heat is transferred at a rate of 0.1 kW through glass wool insulation (density=100kg/m3) with a 5-cm thickness and 2-m2 area. If the hot surface is at 70C, determine the temperature of the cooler surface.1.10 A heat flux meter at the outer (cold) wall of a concrete building indicates that the heat loss through a wall of 10-cm thickness is . If a thermocouple at the inner surface of the wall indicates a temperature of 22°C while another at the outer surface shows 6°C, calculate the thermal conductivity of the concrete and compare your result with the value in Appendix 2, Table 11.
- 1.60 Two electric resistance heaters with a 20 cm length and a 2 cm diameter are inserted into a well-insulated 40-L tank of water that is initially at 300 K. If each heater dissipates 500 W, what is the time required for bringing the water temperature in the tank to 340 K? State your assumption for your analysis.2.55 A long, 1-cm-diameter electric copper cable is embedded in the center of a 25-cm-square concrete block. If the outside temperature of the concrete is 25oC and the rate of electrical energy dissipation in the cable is 150 W per meter length, determine temperatures at the outer surface and at the center of the cable.2.2 A small dam, which is idealized by a large slab 1.2 m thick, is to be completely poured in a short Period of time. The hydration of the concrete results in the equivalent of a distributed source of constant strength of 100 W/m3. If both dam surfaces are at 16°C, determine the maximum temperature to which the concrete will be subjected, assuming steady-state conditions. The thermal conductivity of the wet concrete can be taken as 0.84 W/m K.
- 2.38 The addition of aluminum fins has been suggested to increase the rate of heat dissipation from one side of an electronic device 1 m wide and 1 m tall. The fins are to be rectangular in cross section, 2.5 cm long and 0.25 cm thick, as shown in the figure. There are to be 100 fins per meter. The convection heat transfer coefficient, both for the wall and the fins, is estimated to be K. With this information determine the percent increase in the rate of heat transfer of the finned wall compared to the bare wall.2.9 In a large chemical factory, hot gases at 2273 K are cooled by a liquid at 373 K with gas-side and liquid-side convection heat transfer coefficients of 50 and , respectively. The wall that separates the gas and liquid streams is composed of a 2-cm thick oxide layer on the gas side and a 4-cm thick slab of stainless steel on the liquid side. There is a contact resistance between the oxide layer and the steel of . Determine the rate of heat loss from hot gases through the composite wall to the liquid.A cooling system is to be designed for a food storage warehouse for keeping perishable foods cool prior to transportation to grocery stores. The warehouse has an effective surface area of 1860 m2 exposed to an ambient air temperature of 32C. The warehouse wall insulation (k=0.17W/(mK)) is 7.5 cm thick. Determine the rate at which heat must be removed (W) from the warehouse to maintain the food at 4C.
- Show that the rate of heat conduction per unit length through a long, hollow cylinder of inner radius ri and outer radius ro, made of a material whose thermal conductivity varies linearly with temperature, is given by qkL=TiTo(rori)/kmA where Ti = temperature at the inner surface To = temperature at the outer surface A=2(rori)/ln(ro/ri)km=ko[1+k(Ti+To)/2]L=lenthofcyclinder1.37 Mild steel nails were driven through a solid wood wall consisting of two layers, each 2.5-cm thick, for reinforcement. If the total cross-sectional area of the nails is 0.5% of the wall area, determine the unit thermal conductance of the composite wall and the percent of the total heat flow that passes through the nails when the temperature difference across the wall is 25°C. Neglect contact resistance between the wood layers.One end of a 0.3-m-long steel rod is connected to a wall at 204C. The other end is connected to a wall that is maintained at 93C. Air is blown across the rod so that a heat transfer coefficient of 17W/m2 K is maintained over the entire surface. If the diameter of the rod is 5 cm and the temperature of the air is 38C, what is the net rate of heat loss to the air?