MET 214NATURAL CONVECTION SYSTEMSASMod - 3bP = 0283 kg/m, u = 248 x 10° kg/ms,Pr = 0.683,k= 0.0371 W/m.°C7. A horizontal heated pipe with diameter D= 2 cm is maintained at 60°C in aroom where the temperature is 30°C. Calculate the free convection heat lossper unit length of pipe. The properties of air at the mean film temperatureare a follows:|: 315x 10'K", v= 175x 10'm/,Pr = 0.704,k= 0.0276 W/m'C8. A large vertical plate 2 m high is maintained at 39'C and exposed to air at15°C. Calculate the heat transfer if the plate is 3 m wide. The properties ofair at the mean film temperature are as follows:| = 33x 10'K', v= 157x10° m'/sPr = 0.708 ,k= 0.0262 W/m'C9. A brick wall 20 cm thick of thermal conductivity 5.9 W/mK separates aroom where the air has a temperature of 20°C from the outside where the airtemperature is -18'C. If the convection coefficient on the inside is 4 W/m'.Kand twice as large on the outside, find:a. the overall heat transfer coefficientb. the heat transferred per unit area through the wall.10. A hot water pipe of 4 cm inside diameter, 5 cm thick is made of a materialhaving k = 025W/m.K. If the inside and outside heat transfer ceficientsare 400 and 10 W/mK respectively, calculate the rate of heat loss from waterto the surrounding air if the water and air temperatures are 60 and 20°Crespectively.

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7. A horizontal heated pipe with diameter D = 2 cm is maintained at 60°C in a room where the temperature is 30°C. Calculate the free convection heat loss per unit length of pipe. The properties of air at the mean film temperature are a follows: Pr = 0704, k= 0276 W/m°C

7. A horizontal heated pipe with diameter D = 2 cm is maintained at 60°C in a room where the temperature is 30°C. Calculate the free convection heat loss per unit length of pipe. The properties of air at the mean film temperature are a follows: Pr = 0704, k= 0276 W/m°C

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 7.13P

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