Q2: A 2.5-cm-diameter steel pipe is maintained at 100'C by condensing steam on the inside. The pipe is to be used for dissipating heat to a surrounding room at 20-C by placing circular steel fins around the outside surface of the pipe. The convection loss from the pipe and fins occurs by free convection, with h W/m C. Examine several cases of fin thickness, fin spacing, and fin outside diameters to determine the overall heat loss per meter of pipe length. Take k 43 W/m C for the steel fins and assume h is uniform over all surfaces. = 8.0

Q2: A 2.5-cm-diameter steel pipe is maintained at 100'C by condensing steam on the inside. The pipe is to be used for dissipating heat to a surrounding room at 20-C by placing circular steel fins around the outside surface of the pipe. The convection loss from the pipe and fins occurs by free convection, with h W/m C. Examine several cases of fin thickness, fin spacing, and fin outside diameters to determine the overall heat loss per meter of pipe length. Take k 43 W/m C for the steel fins and assume h is uniform over all surfaces. = 8.0

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.36P

See similar textbooks

Similar questions

A transformer is to be cooled via forced air convection. To increase the effectiveness of thecooling, Alloy 1095 cast aluminum fins are attached to the top of the transformer overwhich air is blown (negligible thermal contact resistance between the transformer and thefins). The fins are 2 cm thick and 7 cm long and span the entire length of the transformer,and the transformer is 7 cm wide and 10 cm long. Air leaves the cooling fan at 25°C .a) Decide how to model the fins before performing any real analysis. Youare willing to accept some error in your analysis and so you will either model thefins as having adiabatic tips or being infinitely long. You expect the average convectioncoefficient over the heat transfer surfaces for this system to be around 50 W m2– K⁄ .Which tip condition should you use for the fins in your analysis? b) Modeling the transformer as being isothermal, determine the average convectioncoefficient over the heat transfer surfaces. Account for heat transfer from the…
An 8-m-internal-diameter spherical tank made of 1.5-cm-thick stainless steelAISI 302 is used to store iced water at 0°C. The tank is located in a roomwith temperature 25°C. The outer surface of the tank is black (emissivity, ε= 1), the heat transfer between the outer surface of the tank and thesurroundings is by natural convection and radiation. The convection heattransfer coefficients at the inner and the outer surfaces of the tank are 80W/m2K and 10W/m2K, respectively; and the outer surface temperature of thetank is 5°C. Draw the equivalent thermal circuit of the system. Determine the total heat transfer rate to the iced water in the tank and the total amount of ice at 0°C that melts after 24 hours.
Experiment No. (5) Heat Transfer, Power Input and Surface temperature 4. In what functions does Nusselt number in natural convection differ from forced convection, Discuss.
please explain brefly in type form Describe the physical mechanism of convection. How is the convection heat-transfer coefficient related to this mechanism?
3- You have experienced convection cooling if you have ever extended your handout of the window of a moving vehicle or into a flowing water stream. With the surface of your hand at a temperature of 30 oC, determine the convection heat flux for a) a vehicle speed of 35 km/h in air at -5 oC with convection coefficient of 40 W/m2 .K and b) a velocity of 0.2 m/s in a water stream at 10 oC with convection coefficient of 900 W/m2.K. Which condition would feel colder? Contrast theseresults with a heat loss of approximately 30 W/m2 under normal room conditions.
Question 1:A glass window of width W = 1 m and height H = 2 m is 5 mm thick and has a thermal conductivity of kg=1.4 W/m.K. If the inner and outer surface temperatures of the glass are 15oC and -20oC, respectively, ona cold winter day, what is the rate of heat loss throughthe glass? To reduce heat loss through windows, it iscustomary to use a double pane construction in whichadjoining panes are separated by an air space. If thespacing is 10 mm and the glass surfaces in contact withthe air have temperatures of (last two digit of your Registration number) oC and -15oC, what isthe rate of heat loss from a 1 m x 2 m window? Thethermal conductivity of air is ka=0.024 W/m.K.
Convection heat transfer from a plate (2 m x 2 m) is 450 W. If surface temperature of plate is 450 K and surrounding temperature is 300 K, what will be value of heat transfer coefficient?
A 5.0-cm-diameter cylinder is heated to a temperature of 200 oC, and air at 30 oC forced across it at a velocity of 50 m/s (h = 180 W/m2K). If the surface emissivity is 0.7, calculate the total heat loss per unit length if the walls of the enclosing room are at 10 oC. Comment on your calculation. COMPLETE SOLUTION
Hi, can you help me to answer this question using the first law of thermodynamics? On a hot summer day a student turns his fan on when he leaves his room in themorning. When he returns in the evening will the room be warmer or cooler than theneighborouing rooms ? Explain your answer using the first law of thermodynamics.Assume ALL doors and windows are kept closed.
Define convection and its types. Either free or forced convection is good by considering an example.
Either free or forced convection is good by considering an example. please explain
Calculate the over-all coefficient of heat transfer U for a piece of glass1/8-in thick, exposed to still air at 70 °F on one side and 0 °F air moving at15 mph on the other side.