2 parts ( A&B) Read and solve carefully please write clearly and box the final answer(s) label themHint: Pay attention to numbers bolded Question : A 100 mm- diameter, thin walled duct covered with a 50 mm-thick layer of insulation (k¡ns= 0.08 W/m.K) is used to carry superheated steam at atmospheric pressure is suspended from theceiling of a large room. The air temperature is at 20 C and natural circulation provides a convectioncoefficient of 10 W/m².K at the outer surface of the covered pipe. The steam enters the pipe at 120 Cand the velocity of the steam is 10 m/s. Evaluating the steam properties at 380 K using Table A.6and assuming the pipe is 10m long, answer the following questionsPart(A) Using Dittus-Boelter correlation (eqn. (8.60)), compute the heat transfer coefficient for theinternal flow?Part (B) What is the temperature of the steam at exit?

INTRODUCTION : Heat losses from the hot fluid always occur when hot steam is conveyed out through…

Question : A 100 mm- diameter, thin walled duct covered with a 50 mm-thíck layer of insulation (ki = 0.08 W/m.K) is used to carry superheated steam at atmospheric pressure is suspended from th ceiling of a large room. The air temperature is at 20 C and natural circulation provides a convectio coefficient of 10 W/m².K at the outer surface of the covered pipe. The steam enters the pipe at 120 and the velocity of the steam is 10 m/s. Evaluating the steam properties at 380 K using Table A. and assuming the pipe is 10m long, answer the following questions art(A) Using Dittus-Boelter correlation (eqn. (8.60)), compute the heat transfer coefficient for th internal flow? rt (B) What is the temperature of the steam at exit?

Question : A 100 mm- diameter, thin walled duct covered with a 50 mm-thíck layer of insulation (ki = 0.08 W/m.K) is used to carry superheated steam at atmospheric pressure is suspended from th ceiling of a large room. The air temperature is at 20 C and natural circulation provides a convectio coefficient of 10 W/m².K at the outer surface of the covered pipe. The steam enters the pipe at 120 and the velocity of the steam is 10 m/s. Evaluating the steam properties at 380 K using Table A. and assuming the pipe is 10m long, answer the following questions art(A) Using Dittus-Boelter correlation (eqn. (8.60)), compute the heat transfer coefficient for th internal flow? rt (B) What is the temperature of the steam at exit?

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.37P

See similar textbooks

Similar questions

(a) If the cost of producing the hot water is $0.10 per kWh, what is the representative daily costof heat loss from an uninsulated pipe to the air per meter of pipe length? The convectionresistance associated with water flow in the pipe may be neglected.(b) Determine the savings associated with application of a 10-mm-thick coating of urethaneinsulation (k = 0.026 W/m-K) to the outer surface of the pipe.
a) What regions show the largest oceanic latent heat loss? b) What regions show the saltiest surface waters? c) What is the main factor affecting the two radiation heat flux terms? Name the two fluxes. d) What is the main factor affecting the two turbulent heat flux terms? Name the two fluxes.
Chips of width L _ 15 mm on a side are mounted to a substrate that is installed in an enclosure whose walls and air are maintained at a temperature of Tsur=T∞=25oC. The chips have an emissivity of ε=0.60 and a maximum allowable temperature of Ts=85oC. (a) If heat is rejected from the chips by radiation and natural convection, what is the maximum operating power of each chip? The convection coefficient may be approximated as h=11.7 W/m2K. (b) If a fan is used to maintain airflow through the enclosure and heat transfer is by only forced convection, with h=250 W/m2K, what is the maximum operating power
pnts) Chips of width L _ 15 mm on a side are mounted to a substrate that is installed in an enclosure whose walls and air are maintained at a temperature of Tsur=T∞=25oC. The chips have an emissivity of ε=0.60 and a maximum allowable temperature of Ts=85oC. (a) If heat is rejected from the chips by radiation and natural convection, what is the maximum operating power of each chip? The convection coefficient may be approximated as h=11.7 W/m2K. (b) If a fan is used to maintain airflow through the enclosure and heat transfer is by only forced convection, with h=250 W/m2K, what is the maximum operating power?
Consider a two-layer sphere with inside fluid convection rate h1 and outer rate h2. The first layer has inside radius r1 and outside radius r2. The second layer has outside radius r3. What is the general equation for the total resistance? Neglect thermal contact resistance.
Can u continue the question 5 to 7 5. Calculate the change in heat energy of the submarine’s outer haul, when it descends from the surface to a depth of 3,500m (with an average temperature of 20°C). 6. Calculate the power of the submarine’s electrical heater needed, to maintain the interior of outer hull at 30°C. The exterior of outer hull is 10°C. (Assume heat of the submarine is only lost across the outer hull) 7. Suggest aerospace applications of ballast.
Fins, or extended surfaces, commonly are used in a variety of engineering applications to enhance cooling. Common examples include a motorcycle engine head, a lawn mower engine head, extended surfaces used in electronic equipment, and finned tube heat exchangers in room heating and cooling applications. Consider aluminum fins of a rectangular profile, which are used to remove heat from a surface whose temperature is100° C . The temperature of the ambient air is 20° C. We are interested in determining how the temperature of the fin varies along its length and plotting this temperature variation. For long fins, the temperaturedistribution along the fin is given by
What is the heat transfer coefficient for ambient air at 43 C
When the convection heat transfer coefficient is very large (h → ∞), the convection resistance becomes zero and Ts ≈ T. This situation is approached in practice at surfaces where ------------------------ occur.
Hot water is to be cooled as it flows through the tubes exposed to atmospheric air. Fins are to be attached in order to enhance heat transfer. Would you recommend attaching the fins inside or outside the tubes? Why?
Steam at a temperature of 723 K is flowing through a pipe with an outer diameter of 100 mm. The pipe is insulated with 30-mm thick mineral wool, the average thermal conductivity of which is 0.065 W/m.K. Determine the outside surface temperature of mineral wool if the ambient air temperature is 300 Assume the hot-surface temperature of the mineral wool is the same as that of the flowing steam and the value of the surface coefficient of the insulating material is 33 W/m2.K.
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.