A sphere ( k=204 W/m K) with inner diameter 4 cm and outer diameter of 8 cm . The inside temperature is 100C and the outer temperature 50 C . Calculate the rate of heat transfer
Q: For heat transfer purposes, a standing man can be modeled as a 30-cm-diameter, 170-cm-long vertical…
A:
Q: A spherical container with an inner radius r1 = 1 m and an outer radius r2 = 1.05 m has its inner…
A: Using differential equation for heat conduction,
Q: A 278-ft-long section of a steam pipe whose outer diameter is 4 inches passes through an open space…
A:
Q: A 50-m-long section of a steam pipe whose outer diameter is 10 cm passes through an open space at…
A:
Q: A 4-mm-diameter, 10-cm-long aluminum fin (k = 237 W/m-K) is attached to a surface. If the heat…
A:
Q: Heat is transferred at a rate of 0.1 kW through glass wool insulation (density= 100 kg/m^3) of 5cm…
A: Answer: The temperature of the cooler surface is 0.6 ℃.
Q: Consider a 20-cm-thick large concrete plane wall (k = 0.77 W/m- "C) subjected to convection on both…
A:
Q: Steam at 280C flows in a stainless steel pipe k = 15 W/m.K whose inner and outer diameter are 5cm…
A:
Q: For heat transfer purposes, a standing man can be modeled as a 30-cm-diameter, 175-cm-long vertical…
A: Given: The convection heat transfer coefficient is h=10 W/m2 °C The diameter of the vertical…
Q: An aluminum pan with a thermal conductivity of = 237 /m.K is used to heat water as shown in the…
A: As per given D=15cm K=237 w/m°c Q=1400w T=105°c We have to determine temperature of outer surface
Q: Q) An apple has been put into a freezer at (-23°C) to be cooled. Initially, the apple is at a…
A: Given:- Surrounding temperature, T∞=-23°C=250K Initial temperature of apple, Ti=15°C=288K…
Q: A 6 cm diameter sphere or cylinder is initially at 100C. Later, this sphere or cylinder was thrown…
A: Given data: The diameter of the sphere is d=6 cm=0.06 m The initial temperature of the sphere is…
Q: 1.)For heat transfer purposes, a standing man can be modeled as a 34.17-cm-diameter, 173.37-cm-long…
A:
Q: Consider a large plane wall of thickness L = 0.4 m, thermal conductivity k=2.3 W/m °C,and surface…
A: L=Large plane wall Thickness=0.4 mk=Thermal Conductivity=2.3 W/m-°CA=Surface Area=20 m2 At…
Q: A pipe in a manufacturing plant is transporting superheated vapor at a mass flow rate of 0.3 kg/s.…
A: Convection heat transfer take place bw solid boundary and flowing fluid. It is of two types:- 1)…
Q: A solid plate, with a thickness of 15 cm and a thermal conductivity of 80 W/m-K, is being cooled at…
A:
Q: The brick wall of a house measures 4 x 7 m and has a thickness of 0.3 m. The thermal conductivity of…
A: given data as per question Dimensions of the brick wall = 4m×7m Thickness of the wall = 0.3 m…
Q: The thermal resistance for a :solid sphere is equal to Non of them (2n k. ro. ri)/(ro-ri) O (2n ro .…
A: Given:- Solid sphere To find:- Thermal resistance
Q: A 5 m long section of a steam pipe whose outer diameter is 10 cm passes through an open space at…
A: Given data: The length of pipe, L=5 m. The diameter of the pipe, d=10 cm. The open space…
Q: A pipe carrying steam of 5 cm inside diameter and 6.5 cm outside diameter is covered with a 2.75 cm…
A:
Q: A 5-cm-external-diameter, 10-m-long hot-water pipe at 80 deg C is losing heat to the surrounding air…
A: Diameter of pipe = 5 cm Length of pipe = 10 m Pipe temperature = 80 C Surface temperature = 5 C Heat…
Q: A person puts a few apples into the freezer at -13°C to cool them quickly for guests who are about…
A: To solve the above problem first of all we have to calculate , Biot number(Bi) and fourier…
Q: = Consider a person standing in a room at 23°C. Determine the total rate of heat transfer from this…
A:
Q: Steam at 320°C flows in a stainless steel pipe (k = 15 W/m-°C) whose inner and outer diameters are 5…
A: Given Radius, r1 = 2.5 cm r2 = 2.75 cm r3 = 5.75 cm
Q: A glass plate at 40°C is heated by passing hot air over it with a convection heat transfer…
A: Temperature difference should not exceed by 5 C, i.e ( T1 - T2 ) = 5 C Thickness (L)= 1mm Area of…
Q: 210: In a nuclear reactor, 1-cm-diameter cylindrical uranium rods cooled by water from outside serve…
A:
Q: kW of heat transfer occurs over an insulation material with a cross-sectional area of 10 m2 and a…
A:
Q: Aspherical container of inner radius rl = 2 m, outer radius r2 = 2.1 m, and thermal conductivity k =…
A: Given: r1 = 2m r2 = 2.1 m k = 30 W/moC h = 18 W/m2 oC
Q: Q1:1 Consider a 1.2-m-high and thermal conductivity is k = 0.78 through this glass window and the t…
A:
Q: EXAMPLE 1 Aspherical container of inner radius rl = 2 m, outer radius r2 = 2.1m, and thermal…
A: Given: The inner radius of container, r1 = 2 m The outer radius oof container, r2 = 2.1 m The…
Q: A pipe carrying steam of 5 cm inside diameter and 6.5 cm outside diameter is covered with a 2.75 cm…
A:
Q: A 14-cm x 20-cm circuit board houses on its surface 100 closely spaced logic chips, each dissipating…
A:
Q: QI/A 5-cm-external-diameter, 10-m-long hot water pipe at 80°C is losing heat to the surrounding air…
A:
Q: A spherical ball of 5.5-cm diameter whose properties are roughly = 0.6 W/m2.°C and a = 0.14x10-6…
A:
Q: A 4-mm-diameter and 10-cm-long aluminum fin (k = 237 W/m.° C) is attached to a surface. If the heat…
A: Given:- Rate of heat transfer by using the equation Q1· = hpkA…
Q: A long pipe carries hot water and loses heat by convection to the surrounding air at To =22 °C and…
A: There are three modes of heat transfer:- 1) conduction heat transfer which is governed by fourier…
Q: A 50-m-long section of a steam pipe whose outer diameter is 10 cm passes through an open space at…
A:
Q: Why does heat transfer increase initially with radius of insulation and then decrease beyond…
A:
Q: Steam at 200ºC flows in a cast iron pipe (k = 80 W/m⋅ºC) whose inner and outer diameters are D1 =…
A:
Q: 8.) A 50-m-long section of a steam pipe whose outer diameter is 10 cm passes through an open space…
A: Given data, Length of the steam pipe, L = 50 m Outer diameter of the steam pipe, D2 = 0.1 m Outer…
Q: A 339-ft-long section of a steam pipe whose outer diameter is 4 inches passes through an open space…
A: GivenLength of pipe=339ftOuter diameter=4inchesSpace temp=50°FSurface temp Ts=297°FAverage heat…
Q: An aluminum pan whose thermal conductivity is 237 W/m °C has a flat bottom with diameter 20 cm and…
A:
Q: Liquid flows in a metal pipe with an inner diameter of D1 = 20 mm and an outer diameter of D2 = 30…
A: heat energy is flowing into the pipe from the surrounding by means of conduction , convection and…
Q: Consider a person standing in a room at 18°C. Determine the total rate of heat transfer from this…
A:
Q: A pipe in a manufacturing plant is transporting superheated vapor at a mass flow rate of 0.3 kg/s.…
A: Write the differential equation for the steady state one dimension heat conduction.
Q: A 339-ft-long section of a steam pipe whose outer diameter is 4 inches passes through an open space…
A:
Q: sof? =120°Cand?
A: given:outer radius r2=7cminner radius r1=5cmthermal conductivity k=25W/mKT1=120CT2=50C
A sphere ( k=204 W/m K) with inner diameter 4 cm and outer diameter of 8 cm . The inside temperature is 100C and the outer temperature 50 C . Calculate the rate of heat transfer
Step by step
Solved in 2 steps with 2 images
- 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.1.19 A cryogenic fluid is stored in a 0.3-m-diameter spherical container is still air. If the convection heat transfer coefficient between the outer surface of the container and the air is 6.8 , the temperature of the air is 27°C, and the temperature of the surface of the sphere is –183°C, determine the rate of heat transfer by convection.3.16 A large, 2.54-cm.-thick copper plate is placed between two air streams. The heat transfer coefficient on one side is and on the other side is . If the temperature of both streams is suddenly changed from 38°C to 93°C, determine how long it takes for the copper plate to reach a temperature of 82°C.
- 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.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.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=lenthofcyclinder
- Consider a steam pipe of length 15 ft, inner radius 2 in., outer radius 2.4 in., and thermal conductivity 7.2 Btu/hr-ft-°F. Steam is flowing through the pipe at an average temperature of 250°F, and the average convection heat transfer coefficient on the inner surface is given to be 1.25 Btu/hr-ft2-°F. If the average temperature on the outer surfaces of the pipe is 160°F, determine the rate of heat loss from the steam through the pipe. ANSWER:______Btu/hr3 kW of heat transfer occurs over an insulation material with a cross-sectional area of 10 m2and a thickness of 2.5 cm. Since the temperature of the inner surface is 415 ºC and the thermal conductivity of the material is 0.2 W/ m.K, calculate the temperature of the outer surfaceA person puts a few apples into the freezer at -13°C to cool them quickly for guests who are about to arrive. Initially, the apples are at a uniform temperature of 37°C, and the heat transfer coefficient on the surfaces is 6.3 W/m2 · °C. Treating the apples as 8.2-cm-diameter spheres and taking their properties to be ρ= 836 kg/m3, Cp = 4.05 kJ/kg · °C, k= 0.426 W/m · °C, and α= 1.43 ×10-7 m2/s, determine the center and surface temperatures of the apples in 1.9 h
- A 5 m long section of a steam pipe whose outer diameter is 10 cm passes through an open space at 30°C. The average temperature of the outer surface of the pipe is measured to be 150°C, and the average heat transfer coefficient on that surface is determined to be 180 W/m^2.k. Determine (a) the rate of heat loss through convection from the steam pipe and (b) the annual cost of this energy loss if steam is generated in a natural gas furnace, and the price of natural gas is 0.05 Rs/Kwh, consider a 250 working-day year.Steam at 320°C flows in a stainless steel pipe (k = 15 W/m-°C) whose inner and outer diameters are 5 cm and 5.5 cm, respectively. The pipe is covered with 3-cm-thick glass wool insulation (k = 0.038 W/m-°C). Heat is lost to the surroundings at 5°C by natural convection and radiation, with a combined natural convection and radiation heat transfer coefficient of 15Wm2-°C. Taking the heat transfer coefficient inside the pipe to be 80 W/m2-°C, determine the rate of heat loss from the steam per unit length of the pipe. Also determine the temperature drops across the pipe shell and the insulation.A person puts a few apples into the freezer at 15°C cool them quickly for guestswho are about to arrive. Initially, the apples are at a uniform temperature of 20°C,and the heat transfer coefficient on the surfaces is 8 W/m2·K. Treating the apples as9-cm-diameter spheres and taking their properties to be 840 kg/m3, Cp 3.81 kJ/kg·K, k = 0.418 W/m·K, and α =10-7 m2/s, determine the center and surface temperatures of the apples in 1 h. Also, determine the amount of heat transfer from each apple. Solve this problem using analytical one-term approximation method (notthe Heisler charts). Answer: Center: 11.2 ℃, Surface: 2.7 ℃, heat transfer: 17.2 kJ