15. Saturated steam at 500°K flows in a 0.20 m inside diameter, 0.21 m outside diameter pipe. The pipe is covered with 0.08 m of insulation with a thermal conductivity of 0.10 W/m-K. The pipe's conductivity is 52 W/m-K. The ambient temperature is 300°K. The unit convective coefficients are hi = 18,000 W/m2-K'and ho = 12 W/m2-K. Determine the heat loss from 4 m of pipe. A. 778.21 watts B. 825.80 watts C. 830.80 watts D. 835.80 watts

15. Saturated steam at 500°K flows in a 0.20 m inside diameter, 0.21 m outside diameter pipe. The pipe is covered with 0.08 m of insulation with a thermal conductivity of 0.10 W/m-K. The pipe's conductivity is 52 W/m-K. The ambient temperature is 300°K. The unit convective coefficients are hi = 18,000 W/m2-K'and ho = 12 W/m2-K. Determine the heat loss from 4 m of pipe. A. 778.21 watts B. 825.80 watts C. 830.80 watts D. 835.80 watts

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.

Chapter10: Heat Exchangers

Section: Chapter Questions

Problem 10.33P

See similar textbooks

Similar questions

1- For the following design conditions:- Condenser heat load (Qc) = 293 MW Condenser Pressure (Pcond) = 0.06 bar Cooling Water inlet temperature (tw,) = 25 C° Cooling Water velocity (Vw) = 2 m/s Number of Passes (N) = Single Tube Diameter (D) Tube Length (L) = 15 m Tubes Cleanliness factor (Fclean) = 0.85 Overall heat transfer coefficient (U,) = 4000 W /m²C°. Calculate the following:- = 25 mm a. Condenser Surface area b. Cooling water mass flow rate c. Condenser effectiveness
11 MWth plant operates at a thermal efficiency of 34%. The waste heat is dumped across a condenser which operates at a shell side pressure of 0.717 psia. For the given information below, determine the condenser tube length. A Coolant Flow Rate 4.81 x 108 Ibm/hr Coolant Inlet Temperature 60 F Number of Tubes 62,832 Lattice triangular Pitch 1.5 inch Tube OD 1 inch Tube ID 0.944 inch Tube Thermal Conductivity 10 Btu/hr-ft-F Condensing Heat Transfer Coefficient 1228 Btu/hr-ft²-F
6- The following reading were taken during a test on a surface condenser: Mean condenser temperature = 35°C Hot well temperature = 30°C Condenser vacuum = 69 cm Hg Barometer reading = 76cmHg Condensation rate = 16 kg/min Cooling water temperature inter = 20 °C Cooling water temperature outlet = 32.5 °C Flow rate being = 37500 kg/h Calculate: a- mass of air present per cubic meter of condenser b- quality of steam at condenser inlet c- vacuum efficiency d- condenser efficiency (condenser heat transfer effeteness)
3. A 6 in x 20 ft uninsulated B.I pipe conveys steam at 385 °F with an average ambient temperature of 85°F. if the cost of the fuel is PhP 250.00 per 106 BTU with the net energy conversion efficiency of 75%, what is the annual cost of the heat lost? For 6 in. pipe schedule 80:Do = 6.625 inDi = 5.761 in For iron:k = 30 BTU/ hr ft °F for the surface coefficients:hi = 1000BTU/ hr ft2°F ho = 2 BTU/hr ft2 °F
AS& Heat Transfer in Steam Heater Water at an average of 70°F is fiowing in a 2-in. steel pipe, schedule 40. Steam at 220°F is condensing on the outside of the pipe. The con vective coefficient for the water inside the pipe is A = 500 btu/h ft2.°F and the con- densing steam cocfficient on the outside is h = 1500 (a) Calculate the heat loss per unit length of1 ft of pipe using resistances. (b) Repcat, using the overall based on the inside area Ap (c) Repeat, using U 13.2- Ans. (a)q= 26 710 btu/h (7.828 kW). (b) Uj = 329.1 btu/h-ft2."F (1869 W/m2. K), (c) U.= 286.4 btu/h ft2.°F (1626 W/m2. K)
a. An air stream passing through a 2-inch (1/6 ft) diameter, thin-walled tube is to be heated by high- pressure steam condensing on the outer surface of the tube at 320 °F. The overall heat transfer coefficient, h between steam and air can be assumed to be 25 Btu/(ft2.hr °F) with the air entering at 100 ft/sec, 10 psia, 40 °F. The air is to be heated to 150 °F. Determine the tube length required. Assuming Rayleigh Line flow, calculate the static pressure change due to heat addition. Also, for the same inlet conditions, calculate the pressure drop due to friction, assuming Fanno flow in the duct with f = 0.018. b. c. d. To obtain an approximation to the overall pressure drop in this heat exchanger, add the two results. Discuss the accuracy of this calculation.
A steam condenser is made of brass tubes,in., 14 gage. There are 150 tubes per pass. The cooling water flows at the rate of 1.52 m/s, entering at 25°C and leaving at 50°C. The condensing heat transfer coefficient is known to be 10,200 W/m²-°C and the inside tube surface coefficient is 6800 W/m²-°C. Steam is being condensed at 77°C. The tubes are not to exceed 3 m in length. Find the number of tube passes and the length of the tubes.
Saturated steam at 3 atm will flow through a 3 in. Schedule 80 steel pipe. In order todecrease the heat losses to the surrounding air (at 20 oC) the pipe will be insulated. There are twotypes of insulating materials available, each with a thickness of 2.5 cm. Thermal conductivity ofinsulator A is 0.04 W/m.K and that of insulator B is 0.20 W/m.K. Both insulators will be used, inorder to have the least heat loss. Which insulator should be covered outside? Assume thatconvective heat transfer coefficient between the insulated pipe and air is 15 W/m2K.
For Heat transfer through cylinder tube wall, the temperature is to be a linear function of r (radius) of the tube. Select one: O True O False The conductivity of H20 in solid form (ice) is higher than that of H20 in liquid form (water). Select one: O True O False F, (Correction factor for temperature in some heat exchangers) should be 1.0 or greater than 1.0 in some cases. Select one: O True False
A four-effect evaporator is being considered for concentratinga fruit juice that has no appreciable boiling-point elevation.Steam is available at 143.27 kPa, and the boiling point of the product in the fourth effect is 45°C. The overall heat-transfer coeffi cients are 3000 W/(m 2 °C) in the fi rst effect, 2500W/(m2 °C) in the second effect, 2100W/(m2°C) in thethird effect, and 1800W/(m2°C) in the fourth effect. Calculatethe boiling-point temperatures of the product in the fi rst,second, and third effects. Assume the heating areas in all theeffects are equal to 50m2 each. The mass fl ow rate of steam tothe fi rst effect is 2400kg/h, the feed rate to the fi rst effect of 5%total solids fl uid is 15,000kg/h, the concentrated product fromthe fi rst effect leaves at 6.25% total solids, and the concentrationof product leaving the second effect is 8.82% total solids. Make it in the form of an example solution spreadsheet .....
The following data were obtained from a test of a surface condenser: Inlet temperature of circulating water = 21°C Outlet temperature of circulating water = 35°C Vacuum in the condenser mm of Hg Compute the efficiency of the condenser. 704.7 mm of Hg Barometer reading 760
In a large student house supply at a pressure of 2 bar, gauge, and at a temperature 10°C. A wash basin cold tap is located 3 meters above the mains supply, connected to the mains pipe with a copper pipe of internal diameter 15 mm and length 12 meters. When the tap is opened the flow rate of water out of the tap is 24 litres per minute, creating a Fanning friction factor in the pipe of 0.008. cold water is supplied by the mains water a) Calculate the Reynolds number of the water in the pipe and determine if it is laminar or turbulent. b) Calculate the pressure loss from friction, change in elevation, and hence the pressure of the water just before entering the tap. c) Name two assumptions that have been made in order to arrive at your answer to part b) and state if these assumptions under or over predict the pressure of the water just before entering the tap. d) If the value were not given, what procedure would be needed to determine the Fanning friction factor?