A rectangular wall of length "L" m and height "H" m is made from a thick bricklayer. The rectangular wall has a surface area as 11 m2 & Thermal conductivity as 0.53 W/mK. The wall is subjected to heat transfer due to the outside temperature 43 °C and inside temperature 24 °C. If the energy loss is 11219 kJ in 484 minutes. (HINT: 1 minute = 60 %3D seconds) Determine the following -- i) Heat transfer rate, ii) Thickness of the wall.
Q: Q: Consider the section of wall as shown in the figure, assuming one dimensional heat flow,…
A:
Q: 7. A 5-m-internal-diameter spherical tank made of 1.5-cm-thick stainless steel (k =15 W/m - °C) is…
A: The area of sphere at inner and outer surface is - Ai=4πri2=4π×2.52=78.54 m2,…
Q: An office space of 12 ft x12 ft x10 ft height. The heat loss through roof is (4780.8 Btuh) if…
A:
Q: For heat transfer purposes, a standing man can be modeled as a 30-cm-diameter, 170-cm-long vertical…
A:
Q: A non-insulated steam pipe passes through a room at 30°C. It has an outside diameter and a…
A:
Q: A hot surface at 100°C is to be cooled by attaching 3-cm-long, 0.25-cm-diameter aluminum pin fins (k…
A: Given: The temperature of hot surface, Ti = 100°C The length of fins, L = 3 cm The diameter of fins,…
Q: If the rate of heat flow through a furnace wall is 0.94 kW/m². The wall consisting of 0.20 m thick…
A:
Q: Q. 4) from the schematic diagram find, (a) Length of fin, (b) Fin effectiveness. Account for tip…
A: (a) Write the given data. ηf=0.65D=4 mmh=220 W/m2Kk=160 W/mK
Q: A thermal window consisting of two panes of 0.25" glass (R-value 0.08 hr · ft?. oF/BTU each),…
A:
Q: The temperature at the inner and outer surfaces of a boiler wall made of 20 mm thick steel and…
A:
Q: Q2/ An aluminum sphere weighting 7kg and initially at a temperature of 533K is suddenly immersed in…
A:
Q: A wall of length "L" m and height "H" m is made from a thick bricklayer of 38 cm with thermal…
A:
Q: If the rate of heat flow through a furnace wall is 0.94 kW/m². The wall consisting of 0.20 m thick…
A: Heat flux will be same across the layers. 1. The temperature of the gases inside the furnace is…
Q: Calculate the convection heat transfer coefficient value on the outer surface of the insulation to…
A: The environment air temperature is, T0=30°C The thickness of the insulating material is, L=4 cm The…
Q: A long pipe carries hot water and loses heat by convection to the surrounding air at T =22 °C and…
A: In general, there are three modes by which heat gets transferred from one place to another. The…
Q: Q3) A total of 10 rectangular aluminum fins (k = 203 W/m.K) are places on the outside flat surface…
A:
Q: Convection heat transfer through the plate is 180 w/m?k. Find convection heat transfer coefficient…
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: Q2/ An aluminum sphere weighting 7kg and initially at a temperature of 533K is suddenly immersed in…
A: Given Data: The mass of the sphere is, m=7 kg. The initial temperature of the sphere is, T1=533°C.…
Q: A wall with a thermal conductivity of 0.4 W/m-°C is maintained at 45°C. The heat transfer through…
A: Givenk=0.4W/moCT1=45oCQ=220WA=2.0m2t=1.5cm
Q: Given: Fin length: 45 mm Fin width: 90 mm Fin thickness: 5 mm Thermal conductivity of fin material:…
A: Given Length, L = 45 mm = 0.045 mm Width, w…
Q: A slab 0.25 m thick with thermal conductivity of 45 w/m-K receives heat from a furnace at 500 K both…
A:
Q: A 2.2 m x 0.98 m x 4.0 cm thick solid wood door has a 0.5 m square window. The window has two panes…
A:
Q: The thermal conductivities of human tissues vary greatly. “Fat” and “skin” have conductivities of…
A: In heat transfer analysis, the rate of change of state is evaluated by calculating the rate of heat…
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 plane wall of thickness 50 cm having thermal conductivity 17.5 W/m°c. temperature at right and…
A: Data given- Thickness ∆x = 50 cm K = 17.5 W/m°C T1 = 150°C T2 = 10°C
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 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: The measure used in a weight-measurement unit in the world is expressed by Q=kadT/dr. Here, A is the…
A:
Q: A long pipe carries hot water and loses heat by convection to the surrounding air at Too=16 °C and…
A:
Q: The measure used in a weight-measurement unit in the world is expressed and k is the heat. A steam…
A: we are to determine the net heat transferred and and the temperature profile in the radial direction…
Q: A solid body have a thermal conductivity(45 W/m.'c) is subjected to steady two-dimensional heat…
A: To calculate the heat loss , we need to find the temperature at node 1 General form of infinite…
Q: What is the heat loss through the windows of a passenger train left outside a station in winter,…
A:
Q: A wall of length "L" m and height "H" m is made from a thick bricklayer of 29 cm with thermal…
A: GIVEN: - wall of length "L" m and height "H" m - thick bricklayer of 29 cm - thermal conductivity…
Q: A plane wall of 0.15m thick and its area is 10 m2. If it's thermal conductivity is 8.45W/m °C and…
A: L = thickness of the wall = 0.15 m A = area = 10 m2 T1 = 65 oC T2 = 35 oC k = thermal conductivity =…
Q: Heat is produced in a long resistance wire q.u= 1.5 W/cm3. The radius of the wire is given as r1=0.3…
A:
Q: A sphere ( k=204 W/m K) with inner diameter 4 cm and outer diameter of 8 cm . The inside temperature…
A:
Q: A cylindrical system compose of two layers carrying hot fluid of 100 °C temperature and 200W/m2.°C…
A: Given data: Fluid temperature, T1 = 100°C. Heat transfer coefficient of fluid, h1 = 200 W/m2·°C.…
Q: A wall of length "L" m and height "H" m is made from a thick bricklayer of 26 cm with thermal…
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: A wall of length "L" m and height "H" m is made from a thick bricklayer of 26 cm with thermal…
A:
Q: A plane wall 3.5 cm thick generates heat internally. The wall is made of a material with thermal…
A:
Q: A thermal window consisting of two panes of 0.25" glass (R-value 0.08 hr · ft2. °F/BTU each),…
A: Given: Glass: t = 0.25 in R = 0.08 hr.ft2F/BTU Air: t = 0.75 in Find: R value in summer and winter
Q: In a warm room, a naked resting person has a skin temperature of 33°C If the room temperature is…
A: skin temp = 33°C =33+273=303Kroom temp=29°C =29+273=302Kbody surface area=1.5m2heat transfer…
Q: Example 2: Double-pane window, each window have: Height = 0.8 m Width 1.5 m Thickness = 4 mm k…
A:
Q: Q1) A polished metal pipe (8 cm) outside diameter and 350 K temperature at the outer surface is…
A: Note: Since you have asked multiple question, we will solve the first question for you. If you want…
Q: A sphere ( k=204 W/m K) with inner diameter 4 cm and outer diameter of 8 cm. The inside temperature…
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:
Step by step
Solved in 2 steps with 2 images
- 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.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.The 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.
- 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=lenthofcyclinderA square silicon chip 7mm7mm 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 temperature difference between the front and back surfaces of the chip. The thermal conductivity of silicon is 150 W/m K. Problem 1.62.38 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.
- A 2 cm thick steel pipe (thermal conductivity 43 W/[m °C]) with 6 cm inside diameter is being used to convey steam from a boiler to process equipment for a distance of 40 m. The inside pipe surface temperature is 115°C, and the outside pipe surface temperature is 90°C. If there is 600kW of heat loss, what is the thickness of the pipe?4.) A 15-cm-diameter steam line carries saturated steam at 6 MPa and is located in a tunnel with stagnant air with a temperature of 50oC. The outside unit convective coefficient is 8.5 W/m2-K. The steam line is covered with 3 cm of 85% magnesia insulation. It is decided to reduce the heat loss by one-half. How much 85% magnesia insulation is required? Neglect thermal resistance of pipe and inside surface.Q1) A polished metal pipe (8 cm) owtside diameter and 350 K temperature at the outer surface is exposed to ambient conditions at 285 K temperature. The emissivity of the surface is 0.3 and the convection coefficient of heat transfer is 13.5 Wim2-deg. What would be the overall coefficient of heat transfer by the combined mode of convection and radiation” Q2 find the pressure point (1) if the amospheric pressure is(70kpajihl =0 2,h2=0.4,h3=0. ‘)(p. =13600kg/m3. poil=850kg/m3)
- A freezer of dimensions 4 m wide, 6 m long and 3 m high is under construction. The walls and ceiling are composed of 1.7 mm stainless steel (k = 15 W / [m ° C]), 10 cm thick foam insulation (k = 0.036 W / [m ° C]), certain thickness of corkboard (k = 0.043 W / [m ° C]), and 1.27 cm thick wood (k = 0.104 W / [m ° C]). The inside of the freezer is maintained at -30 ° C. The ambient air outside the freezer is 32 ° C. The convective heat transfer coefficient is 5 W / (m K) on wooden walls and 2 W / (m² K) on stainless steel surfaces. If the outside air has a dew point of 29 ° C, calculate the thickness of the corkboard insulation that will prevent moisture condensation on the outer walls of the freezer. Calculate the rate of heat transfer through the walls and ceiling of this freezer. Ignore heat transfer from floors and corners of buildings. a. Thickness of corkboard insulation = Answercm. b. Heat transfer rate through walls and ceilings = Answerwatt.spherical shaped vessel of 14 m outer diameter is 90 mm thick Find the rate of heat leakage, if the temperature difference between the inner and outer surfaces is 220°C Thermal conductivity of the material of the sphere is 0.083 W/mKA freezer of dimensions 4 m wide, 6 m long and 3 m high is under construction. The walls and ceiling are composed of 1.7 mm stainless steel (k = 15 W / [m ° C]), 10 cm thick foam insulation (k = 0.036 W / [m ° C]), a specific thickness of corkboard (k = 0.043 W / [m ° C]), and 1.27 cm thick wood (k = 0.104 W / [m ° C]). The inside of the freezer is maintained at -30 ° C. The ambient air outside the freezer is 32 ° C. The convective heat transfer coefficient is 5 W / (m K) on wooden walls and 2 W / (m² K) on stainless steel surfaces. If the outside air has a dew point of 29 ° C, calculate the thickness of the corkboard insulation that will prevent moisture condensation on the outside walls of the freezer. Calculate the heat transfer rate through the walls and ceiling of this freezer. Ignore heat transfer from floors and corners of buildings. a. Thickness of corkboard insulation = cm. b. Heat transfer rate through walls and ceiling = watts.