Fins are used to improve heat transfer by increasing the effective * surface area TRUE O False O
Q: What is the critical radius of insulation for a sphere equal to? k = thermal conductivity in W/m-K h…
A: Let k = Thermal conductivity and h = Heat transfer coefficient. Critical radius of insulation for…
Q: local heat transfer coefficient
A: Given; Free stream velocity is U∞ and the free stream temperature T∞it is lower than the cylinder…
Q: Blowtorch is used to connect the two pipes together. Length of the pipe section shown is 95 cm with…
A: Given: l=0.95m; d=0.65m; t=2.5mm k=157 W/m2K; ambient temperature 20 deg C; h=20 W/mC; and melting…
Q: Q2: A circular tube transmits hot oil at 250-C inside a 10-cm-inside-diameter tube such that hi 2000…
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Q: Steam flows through tubes whose outer radius is 2.5 cm and whose wall are maintained at a…
A: given tube whose outer radius is, r= 2.5 cmwall are maintained at a temperature,T=135occonductivity…
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A:
Q: loublé-pipè cõûñtër-flöw ow hea order to enhance heat transfer, the length of the hea s now doubled.…
A: given: 3-77C Consider a double-pipe counter-flow heat ex changer. In order to enhance heat transfer,…
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A: Given :- thickness of concrete wall (L) =200 mm (or) 0.2 m surface…
Q: Calculate the heat transfer rate per unit area of a 200 mm thick concrete wall at a surface…
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Q: A 0.5-m-diameter pipe (e = 0.9) carrying steam has a surface temperature of 500 K (see Fig. 1.25).…
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Q: An oil radiator has an outside surface area of 0.18 m2 and operates at a surface temperature of 85…
A:
Q: Blowtorch is used to connect the two pipes together. Length of the pipe section shown is 80 cm with…
A: Given: l=0.8m; d=0.7m; t=3mm; k=177 W/m2K; ambient temperature is 25 C; h=20 W/mK; Tb=220 C
Q: Fin increase the heat transfer rates by increasing ………………………….
A: Fin increase the heat transfer rates by increasing …………………………. answer the surfce area of the body
Q: What is temperature distribution inside the rod in-terms of "heat generation: g surface…
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Q: Calculate the place remperature for a flat-plate collector whose properties are given below,…
A: To find: The plate temperature for a flat plate collector. Given: The mean glass temperature is…
Q: based on the information given here. Steam in a heating system flows through tubes whose outer…
A: Given Surface area, A = 0.001916 m2 Thermal conductivity, k = 186 W/ moC…
Q: Heat Transfer Consider a infinitely long pin fin with uniform Ac cross sectional area Write ef…
A: Given data Write effectiveness and efficiency for infinitely long pin fin with uniform Ac cross…
Q: 1.29. Delermine the thermal conductivity of carbon monoxide gas at 1 atm pressure and 93.7 °C. Ans…
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Q: What is the thermal resistance of a spherical shell with 12 in OD and an internal radius of 5 in.?…
A: Q)Given dataouter diameter of spherical shell=12ininner radius=5ink=25btu/hr ft.FTo…
Q: Straight, rectangular cross-section fins made of metal with constant thermal conductivity k = 235…
A: (a) Fin efficiency, ηfin = 80.57%. (b) Heat transfer rate from fin, qfin = 444.83 W.
Q: An office space contains one (6'x 3') well- fitted door made of nominal 2" wood. The heat loss…
A: Given data: Tbi=80° F=299.817 KTo=-10° F=249.817 KA=6×3 ft2=1.67225 m2t=2 in=0.0508 mQ=517.2…
Q: Blowtorch is used to connect the two pipes together. Length of the pipe section shown is 150 cm with…
A: Given data: Here, L represents the length, di represents the internal diameter, t represents the…
Q: .A heat pump design creates a heating effect of 35 kW while using 15 kW of electrical power. he…
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Q: A PUC is considering a subsidy program to encourage consumers to install improved insulation in…
A: Given data: Insulation program cost = $1,500,000 Saved power = 5,000 MWh carbon dioxide = 1,135…
Q: thickness (in meter) of the wall to maintain a steady heat flux of 2500 W/m2 should be
A: Given data;
Q: The amount of heat flow through a body by conduction is Directly proportional to the surface area of…
A: As per Fourier's law of heat transfer, amount of heat flow rate is given by, Q = k A ∆T∆x Here, Q =…
Q: An oil radiator has an outside surface area of 0.18 m2 and operates at a surface temperature of 85…
A: GIVEN DATA- AREA A=0.18m2 T1=85'C T2=16'C h=38.25 W/m2K
Q: A hot fluid is being conveyed through a long pipe of 4 cm outer diameter and covered with 2 cm thick…
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Q: 150 circular copper wings ( k=400 W/m C) with a diameter of 5 cm and a thickness of 1 mm were…
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Q: A thin brass pipe, 3 cm in outside diameter, carries hot water at 85°C. It is proposed to place 0.8…
A: Givan Data :- Dp =3cm Tw=85°C Tinf = 22°C Dfins = 8cm
Q: A ball made of steel alloy with a diameter of 2 millimeters is first heated to 800 degrees and then…
A: Given: Diameter of the ball (d)=2mmInitial temperature of the ball (Ti)=800°CTemperature of the…
Q: Describe each of the three methods of heat transfer, in your own words. Make sure to explain how you…
A: As per given We have to describe a. Conductionb. Convectionc. Radiation
Q: increase in the rate of heat transfer of the finned wall compared to the bare wall.
A: Given: h= 1 m w= 1 m Fin: L=2.5 cm =0.025 m t=0.25 cm= 0.0025 m h=35 W/m2K no of fins =100 To…
Q: By using fins, we all of the above O none of the above decrease the ambient temperature increase…
A: By using fins we increase the surface area of the object, And when we increase the surface area the…
Q: Water with a velocity of 1 m/s through a pipe with an inner diameter of 32 mm and an outer diameter…
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Q: Two pin fins are identical, except that the diameter of one of them is twice the diameter of the…
A: (a) The effectiveness of a fin can be expressed as, The ratio of effectiveness can be calculated…
Q: 3- Compare the value between the the actual heat transfer rate Qactual for the surface with fins and…
A: “Since you have asked multiple question, we will solve the first question for you. If you want any…
Q: Which of the following is true for a large heat transfer coefficient? A. It is equivalent to a zero…
A: Heat transfer coefficient is the heat transfer per unit area per unit temperature. The heat transfer…
Q: A) If you increase cross-sectional area effectiveness will drop B) epsilon is proportional to…
A: Option c is correct none of the above
Q: Pin fins are provided to increase the heat transfer from a hot surface. The perimeter of each fin is…
A: Arrangement 2 will have higher heat transfer rate.
Q: he convection heat transfer coefficient between a surface at 40°C and air at 20°C is 20 W⁄m2 − K.…
A: Given Heat transfer coefficient, h = 20 W⁄m2.K Initial Temperature, T1 = 40°C…
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- 10.8 The heat transfer coefficient of a copper tube (1.9-cm II) and 2.3-em OD) is on the inside and on the outside, but a deposit with a fouling factor of (based on the tube outside diameter) has built up over time. Estimate the percentage increase in the overall heat transfer coefficient if the deposit were removed.A boiler tube (OD = 3.5 in., ID = 2.7 in) contains water at 1250 psia (tsat = 572 0F). The water film coefficient is hi = 2000 Btu/hr.ft2.0F when the heat flux is 52000 Btu/hr.ft2 of the outside tube surface. Determine: (a) the outside tube temperature, (b) the permissible thickness of boiler scale if the metallic temperature is not to exceed 925 deg F. Thermal conductivities are: steel, k = 310 and for scale k = 3.5 Btu-in/hr.ft2.0F. Draw the diagramA stainless steel tube (AISI 304) with 36 mm internal diameter and 2mm wall thickness is used for transporting a fluidrefrigerated. The fluid is kept at 6oC and the ambient air is at 23oC, being the convective coefficients of the inner and outer sides equal to 100 W/(m2 oC) and 50 W/(m2 oC), respectively. A) If a 10 mm insulating layer is inserted into the surfaceexposed pipe (kiso=0.050 W/(m.K)), what will be the heat gainper unit of tube length and the new temperature of theexposed surface?
- Based on the picture above, make a schematic and determine the average temperature difference over the entire length of the tube (ATLM). (value 25)A refrigerant 22 condenser has four water passes and a total of 60 copper tubes that are 14 mm ID and have 2 mm wall thickness. The conductivity of copper is 3 90 W/m • K. The outside of the tubes is finned so that the ratio of outside to inside area is 1.7. The cooling-water flow through the condenser tubes is 3.8 L/s (a) Calculate the water-side coefficient if the water is at an average temperature of 30°C, at which temperature k = 0.614 W/m • K, p = 996 kg/m3 , andµ= 0.000803 Pa• s (b) Using a mean condensing coefficient of 1420 W/m2 • K, calculate the overall heat-transfer coefficient based on the condensing area.An industrial freezer is designed to operate with an internal air temperature of -20°C when the external air temperature is 27°C, and the internal and external heattransfer coefficients are 8 W/m2 -K and 12 W/m2 -K, respectively. The walls of thefreezer are composite construction, comprising an inner layer of plastic (k = 0.33 W/m-K, and thickness of 10 mm), and an outer layer of stainless steel (k = 15 W/m-K, and thickness of 3 mm). Sandwiched between these two layers is a layer of insulation material with k = 0.07 W/m-K. Find the width (mm) of the insulation thatis required to reduce the convective heat loss to 60 W/m2.
- To cool a storehouse in the summer without using a conventional air-conditioning system, the owner decided to hire an engineer to design an alternative system that would make use of the water in the nearby lake. The engineer decided to flow air through a thin smooth 10-cm-diameter copper tube that is submerged in the nearby lake. The water in the lake is typically maintained at a constant temperature of 15°C and a convection heat transfer coefficient of 1000 W/m2?K. If air (1 atm) enters the copper tube at a mean temperature of 30°C with an average velocity of 2.5 m/s, determine the necessary copper tube length so that the outlet mean temperature of the air is 20°C.A non-thermally insulated industrial water vapor pipe is 25 m long and 100 mm in diameter. This line crosses a building whose walls and ambient air are at 25oC. Pressurized steam holds the tube surface at 150oC and the convective coefficient is 10 W/(m.K). The surface emissivity is ε=0.8. (a) the heat loss on this line; (b) if the steam is generated in a boiler that operates at 90% efficiency and uses natural gas priced at $0.20/MJ, what is the annual cost of this heat loss? Answer: (a) 18.41 W; (b) $129,000A square isothermal chip is of width 5mm on a side mounted in a substrate such that its side and back surfaces are well insulated, while the front surface is exposed to the flow of coolant at 15C. From reliability considerations, the chip temperature must not exceed 85C. If air is used as a coolant, h = 200W/m2. If a dielectric liquid is used as coolant, h = 3000W/m2. What is the difference in maximum allowable power through the chip between the two coolants? (answer in W) *
- It is proposed to cool oil in a counter-current, concentric tube heatexchanger composed of a thin-walled inner tube of 0.02 m diametercarrying oil and thin-walled, perfectly insulated outer tube of 0.05 mdiameter carrying water. The oil flow rate is 50.0 kg min-1 and it has to becooled from 90°C to 40°C using 60 kg min-1 water at 20°C. Calculate the heat load and the outlet water temperature.[I asked this question previously, but the responce was incorrect] I was advised to input equations (smooth tubes : f=0.790 ln Re - 1.64)^2 3000<Re<5x10^6 and Nu=0.125(Re)(Pr)^1/3 In the effort to find the best way to cool a smooth thin-walled copper tube, an engineer decided to flow air either through the tube or across the outer tube surface. The tube has a diameter of 6 cm, and the surface temperature is maintained constant. Determine the convection heat transfer coefficient when air is flowing through a thin-walled tube at 25 m/s with bulk mean temperature of 50°C. _____ w/m^2kWater is to be heated from 35 °C to 65 °C in a rough tube with a relative roughness of 0.001. The tube has an electric heater provides a constant heat flux such that the tube average wall temperature is 20 °C above the average water bulk temperature. The Reynolds number used for calculating the heat-transfer coefficient is 100,000. Calculate the length of tube required for heating, expressed in meters, if the tube has a diameter of 1 cm.