Example 1.4 length. It is lined inside with 3 cm of insulating material of k = 0.042 W/mK. It is flying at a height where the average outside temperature is - 30°C. To find: The rate of heating required to maintain the compartment at 20°C for passenger comfort. Given: A jet aircraft compartment is assumed to be a cylindrical tube of 3-m diameter and 20-m
Q: An insulated steam pipe located where the ambient temperature is 32°C, has an inside diameter of 50…
A: As per given question Given data T=32°c ho=12 w/m2m Id=50mm Ti=150°c hi=6000 w/m2m We have to…
Q: The rear window of an automobile is defogged by passing warm air over its inner surface. If the warm…
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Q: 1. A simple cavity wall consists of two brick layers separated by an air gap of 50 mm. If the inside…
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Q: An insulated steam pipe located where the ambient temperature is 32°C, has an inside diameter of…
A: T1=150'C T2= 32'C r1=25mm r2=35mm r3=62.5mm kpipe=45W/mK kins=0.12W/mK
Q: A simple cavity wall consists of two brick layers separated by an air gap of 50 mm. If the inside…
A:
Q: You would like to use straight pin fins, with a diameter of 6 mm and length of 4 cm, to cool a…
A: Given, Pin fin dimensions d=6 mm L=4 cm k=205 W/m oC h=25 W/m2 oC No. of fins N=25 Baseplate…
Q: The figure shows a cylindrical shell very long, of length L, very internal radius large r1, outer…
A: The figure shows a cylindrical shell very long, of length L, very internal radius large r1, outer…
Q: Natural Convection Cooling of an Orange.An orange 102 mm in diameter having a surface temperature of…
A: GivenTw=21.1°CTD=4.4°CD=102mm=0.102mR=0.051m
Q: AN PIPE LOCATED WHERE THE AMBIENT TEMPERATURE IS 32 DEG C, HAS AN INSIDE DIAMETER OF 50 mm WITH 10…
A: Given:r1=25 mmr2=35 mmr3=62.5 mmhi=6000 W/m2.Kho=12 W/m2.KKi=45 W/m.Kk2=0.12 W/m.KTi=150 CTo=32 C
Q: A food product with 80% moisture content in a 5 cm diameter can wants to be frozen. The density of…
A: GIVEN:tank diameter, d=5cmdensity, p=1000kg/m3area, A=πdlvolume, V=πd2l4initial temp., T=-1.75'C…
Q: A long wire of diameter D = 2 mm is submerged in an oil bath of temperature T∞ = 23°C. The wire has…
A: Given Current, I = 180 A Resistance, Re = 0.01 Ω/m Diameter, D = 2 mm…
Q: A thermopane window consists of two pieces of glass The window separates room air at 20°C from…
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Q: silicon chip is encapsulated so that, under steady-state conditions, all the power dissipated by it…
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Q: Q2/ A thermopane window consists of two pieces of glass 7 mm thick that enclose an air space 7 mm…
A: T∞i=20°C ,hi=10 Wm2-KKG=1.4 Wm-K, Kair=.0245 WmKh0=80 Wm2K,T∞0=-10°CL=L1=L2=L3=.007 m and A=.8×.5…
Q: An insulated steam pipe located where the ambient temperature is 32°C, has an inside diameter of 50…
A: Given data:
Q: A double window called thermopane is one in which two layers of glass are used separated by a layer…
A: Given Data The change in temperature is: ∆T=27.8 K The thickness of the glass is: xgGlass=6.35 mm…
Q: Metal vapor pipe with an outer diameter of 30 mm has a surface temperature of 400 k and will be…
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Q: Example 7. The temperature distribution within the thermal boundary layer over a flat plate is as T…
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Q: The rear window of an automobile is defogged by passing warm air over its inner surface. If the warm…
A:
Q: The engine cylinder of a motorcycle is constructed of aluminum alloy ((T= 400 Kk 186 W/m. K) and is…
A: Given Data : k = 186 W/mK Height H = 0.15 m Outside diameter d = 50 mm radius r = 25 mm Outside…
Q: Consider 469 mm × 447 mm window in an aircraft. For a temperature difference of 98°C from the inner…
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Q: wo walls of cold storage plant are composed of an insulating material (k = 0.25 kJ/hr-m-°C), 100mm…
A: Given length l(1)=100 mm=0.1 m, k(1)=0.25 kJ/hr-m-degree C length l(2)=15mm=0.015 m, k(2)=3.5…
Q: Calculate the quantity of heat conducted per minute through a duralumin circular disc 127 mm…
A: Given data as per the question Diameter of the disc =127 mm The thickness of the disk = 19 mm…
Q: A 10 cm outer diameter pipe carrying saturated steam at a temperature of 195C is lagged to 20 cm…
A: Given Data :- Find :-D1=10 cm mass of…
Q: A cylindrical pipeline that is used for the transport of crude oil is buried in the soil…
A: Given:- h=1.5m d=0.5m t=100mm=0.2m T0=100°C Ts=0°C kg=0.07 W/m.K ke=0.5 W/m.K To find:- Heat loss…
Q: A 20-çm diameter sphere has a surface temperature of 500 K. The sphere is suspended in 300 K still…
A: Given data as per question Diameter of the sphere =20 cm =0.2 m The surface temperature of sphere…
Q: Q2: A 2.5 -mm-diameter electrical wire is insulated by a 2-mm-thick rubberized sheath (k = 0.11 W/m…
A: In-plane slab, the addition of insulation always reduced the heat loss. But in the case of cylinder…
Q: Window height (0.8 m) and width (1.5 m) consisting of two layers of glass (k = 0.78 W /m Co)…
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Q: 8- A thin square plate with the dimensions of 0.6(m)×0.6(m) is placed in a room with a temperature…
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Q: thick-walled tube of stainless steel [18% Cr, 8% Ni, k = 19 W/m · ◦C] with 2-cm inner diameter (ID)…
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Q: (a) Calculate the R-value of a thermal window made of two single panes of glass each 0.125 in. thick…
A: Heat transfer through wall Heat transfer rate in conduction in wall is directly proportional to…
Q: An electrical heater 100 mm long and 5 mm in diameter is inserted into a hole drilled normal to the…
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Q: Problem 3 An annular aluminum (k = 240 W/m.K) fin of rectangular profile is attached to a circular…
A: An annular aluminum (k = 240 W/m.K) fin of rectangular profile is attached to a circular tube that…
Q: An electric heater in the form of a horizontal disc 0.192 m in diameter is used to heat the bottom…
A: Given: d=0.192m The temperature of engine oil=5°C The temperature of heater surface=70°C To find:…
Q: Consider the use of straight, stainless steel (304) fin of rectangular profile on a plane wall whose…
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Q: The exhaust duct from a heater has an inside diameter of 114. mm with ceram. The average k =1.52…
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Q: An overhead 65-m-long, uninsulated industrial steam pipe of 80 mm diameter is routed through a…
A: Given DataTs=200°CT∞=30°Ch=15W/m2Kε=0.6L=65mD=80mm
Q: The walls of a refrigerator are typically constructed by sandwiching a layer of insulation between…
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Q: An insulated steam pipe located where the ambient temperature is 32°C, has an inside diameter of…
A: Given:…
Q: Q2/ A thermopane window consists of two pieces of glass 7 mm thick that enclose an air space 7 mm…
A:
Q: One side of refrigerated cold chamber is 6 m long by 3.7 m high and consists of 168 mm thickness of…
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Q: 3. A pipe 200 mm outside diameter and 20 m length is covered with a layer, 70 mm thick of insulation…
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Q: The rear window of an automobile is defogged by passing warm air over its inner surface. If the warm…
A:
Q: The rear window of an automobile is defogged by passing warm air over its inner surface. If the warm…
A:
Q: Thermal jackets are typically put on cryogenic storage tanks to minimize the heat transfer gains…
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Q: A rectangular slab of butter which is 46.2 mm thick at a temperature of 277.6 K in a cooler is…
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Q: Consider a carton of milk that is refrigerated to a temperature of TL = 5°C. The temperature in the…
A: we know that emissivity = reflectivity so only 1-0.9 i.e 0.1 fraction of the heat is absorbed also…
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- 3.10 A spherical shell satellite (3-m-OD, 1.25-cm-thick stainless steel walls) re-enters the atmosphere from outer space. If its original temperature is 38°C, the effective average temperature of the atmosphere is 1093°C, and the effective heat transfer coefficient is , estimate the temperature of the shell after reentry, assuming the time of reentry is 10 min and the interior of the shell is evacuated.2.42 A circumferential fin of rectangular cross section, 3.7-cm OD and 0.3 cm thick, surrounds a 2.5-cm- diameter tube as shown below. The fin is constructed of mild steel. Air blowing over the fin produces a heat transfer coefficient of K. If the temperatures of the base of the fin and the air are and , respectively, calculate the heat transfer rate from the fin.The air-conditioning system in a Chevrolet van for use in desert climates is to be sized. The system is to maintain an interior temperature of 20C when the van travels at 100 km/h through dry air at 30C at night. If the top of the van is idealized as a flat plate 6 m long and 2 m wide and the sides as flat plates 3 m tall and 6 m long, estimate the rate at which heat must be removed from the interior to maintain the specified
- An electrical transmission line of 1.2-cm diameter carries a current of 200 amps and has a resistance of 310-4 ohm per meter of length. If the air around this line is at v, determine the surface temperature on a windy day, assuming a wind blows across the line at 33 km/h.A spherical communications satellite, 2 m in diameter, is placed in orbit around the earth. The satellite generates 1000 W of internal power from a small nuclear generator. If the surface of the satellite has an emittance of 0.3, and is shaded from solar radiation by the earth, estimate its surface temperature.Determine the rate of heat transfer per meter length from a 5-cm-OD pipe at 150C placed eccentrically within a larger cylinder of 85 magnesia wool as shown in the sketch. The outside diameter of the larger cylinder is 15 cm and the surface temperature is 50C.
- The heat transfer coefficient for a gas flowing over a thin float plate 3-m long and 0.3-m wide varies with distance from the leading edge according to hc(x)=10x1/4Wm2K If the plate temperature is 170C and the gas temperature is 30C, calculate (a) the average heat transfer coefficient, (b) the rate of heat transfer between the plate and the gas, and (c) the local heat flux 2 m from the leading edge. Problem 1.18The handle of a ladle used for pouring molten lead is 30 cm long. Originally the handle was made of 1.9cm1.25cm mild steel bar stock. To reduce the grip temperature, it is proposed to form the handle of tubing 0.15 cm thick to the same rectangular shape. If the average heat transfer coefficient over the handle surface is 14 W/m K, estimate the reduction of the temperature at the grip in air at 21C.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?
- 1.4 To measure thermal conductivity, two similar 1-cm-thick specimens are placed in the apparatus shown in the accompanying sketch. Electric current is supplied to the guard heater, and a wattmeter shows that the power dissipation is 10 W. Thermocouples attached to the warmer and to the cooler surfaces show temperatures of 322 and 300 K, respectively. Calculate the thermal conductivity of the material at the mean temperature in W/m K. Problem 1.4The rear window of an automobile is defogged by pass- ing warm air over its inner surface. (a) If the warm air is at T ,i 40 C and the correspond- ing convection coefficient is hi 30 W/m2 K, what are the inner and outer surface temperatures of 4-mm-thick window glass, if the outside ambient air temperature is T ,o 10 C and the associated con- vection coefficient is ho 65 W/m2 K? In practice T ,o and ho vary according to weather conditions and car speed. For values of ho 2, 65, and 100 W/m2 K, compute and plot the inner and outer surface temperatures as a function of T ,o for –30 T ,o 0 C.A flat isothermal computer chip has square cross-section of 1 cm x 1 cm, and is mounted on a board that insulates the chip on its sides and bottom. The top surface is exposed to a flowing coolant at 10°C, and corresponding convection coefficient h = 1000 W/m2·K. In order for the computer chip to safely operate, its temperature cannot exceed 65°C. What is the maximum allowable chip power?