Liquid water enters a 10-m-long smooth rectangular tube with a -50 mm and b = 25 mm. The surface temperature is kept constant, and water enters the tube at 20°C with a mass flow rate of 0.25 kg/s. Determine the tube surface temperature necessary to heat the water to the desired outlet temperature of 80°C Find the pumping power. Te

Liquid water enters a 10-m-long smooth rectangular tube with a -50 mm and b = 25 mm. The surface temperature is kept constant, and water enters the tube at 20°C with a mass flow rate of 0.25 kg/s. Determine the tube surface temperature necessary to heat the water to the desired outlet temperature of 80°C Find the pumping power. Te

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 7.4P

See similar textbooks

Similar questions

7.43 Liquid sodium is to be heated from 500 K to 600 K by passing it at a flow rate of 5.0 kg/s through a 5-cmID tube whose surface is maintained at 620 K. What length of tube is required?
3. Consider a 10-m-long smooth rectangular tube, with a =50 mm and b =25 mm, that is maintained at a constant surface temperature. Liquid water enters the tube at 20°C with a mass flow rate of 0.01 kg/s. Determine the tube surface temperature necessary to heat the water to the desired outlet temperature of 80°C.
Consider an air solar collector that is 1 m wide and 5 m longand has a constant spacing of 3 cm between the glass cover andthe collector plate. Air enters the collector at 30°C at a rate of0.15 m3/s through the 1-m-wide edge and flows along the 5-mlong passage way. If the average temperatures of the glasscover and the collector plate are 20°C and 60°C, respectively,determine (a) the net rate of heat transfer to the air in thecollector and (b) the temperature rise of air as it flows throughthe collector.
Combustion gases passing through a 5-cm-internal-diameter circular tube are used to vaporize waste water at atmospheric pressure. Hot gases enter the tube at 225 kPa and 250oC at a mean velocity of 2.5 m/s, and leave at 150o If the average heat transfer coefficient is 150 W/m2K and the inner surface temperature of the tube is 110oC, determine (a) the tube length and (b) the rate of evaporation of water.
Air at 60°C leaves a furnace and passes through a 12-m long, 20-cm × 20-cm square duct at an average velocity of 4 m/s. If the duct has a constant surface temperature of 33°C, determine the exit temperature of the air and the rate of heat transfer.
One house owner with a pond on his property has decided to use the pond water to cool his house. His idea is to flow air through a thin smooth 10-cm-diameter copper tube that could be submerged into the pond. The water in the pond, at few meters below the surface is typically maintained at a constant temperature of 15°C. If he assumes the air (~1 atm) entering 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 that would be needed so that the outlet mean temperature of the air is 20°C. You may consider the convection heat transfer coefficient of 1000 W/m2·K on the outer surface of the copper tube, between the pond water and copper tube. Since the copper tube is thin, the conduction resistance of the tube wall may be neglected.
Liquid glycerin is flowing through a 25-mm-diameter and 10-m-long tube. The liquid glycerin enters the tube at 10°C with a mass flow rate of 0,2 kg/s. If the outlet mean temperature is 60°C and the tube surface temperature is constant, determine the surface temperature of the tube.
Glycerin at 40°C with ρ = 1252 kg/m3 and μ = 0.27 kg/m·s is flowing through a 3.5-cm-diameter horizontal smooth pipe with an average velocity of 3 m/s. Determine the following: The pressure drop per 10 m of the pipe The pumping power requirement
Air enters a 25-cm-diameter 12-m-long underwater duct at 50°C and 1 atm at a mean velocity of 7 m/s, and is cooled by the water outside. If the average heat transfer coefficient is 85 W/m2?K and the tube temperature is nearly equal to the water temperature of 10°C, determine the exit temperature of air and the rate of heat transfer. Evaluate air properties at a bulk mean temperature of 30°C. Is this a good assumption?
Consider a 50-mm-diameter and 25-m-long smooth tube that is maintained at a constant surface temperature. Fluids enter the tube at 30oC with a mass flow rate of 0.02 kg/s. Determine the tube surface temperatures necessary to heat water, engine oil, and liquid mercury to the desired outlet tem-perature of 170o
A 6-m-tall chimney is to bedesigned to discharge hot gases from a fireplace at 1808C at aconstant rate of 0.15 m3/s when the atmospheric air temperatureis 208C. Assuming no heat transfer from the chimney and takingthe chimney entrance loss coefficient to be 1.5 and the frictioncoefficient of the chimney to be 0.020, determine the chimneydiameter that would discharge the hot gases at the desired rate.Note that P3 = P4 = Patm and P2 = P1 = Patm + ratm air gh, andassume the hot gases in the entire chimney are at 180°C.
Glycerin at 40°C with ? = 1252 kg/m3 and ? = 0.27 kg/m·s is flowing through a 6-cm-diameter horizontal smooth pipe with an average velocity of 3.5 m/s. Determine the pressure drop per 10 m of the pipe.