e- Water at 12 °C is to be heated to 60 °C by passing it over a bundle of 3-m-long, 2-cm-diameter resistance heater rods maintained at 95 °C. Water approaches the heater rod bundle in normal direction at a mean velocity of 1.2 m/s. The rods are arranged in-line with longitudinal and transverse pitches of SL = 4 cm and ST = 3 cm. Calculate the number of tube rows NL in the flow direction needed to achieve the indicated temperature rise.

e- Water at 12 °C is to be heated to 60 °C by passing it over a bundle of 3-m-long, 2-cm-diameter resistance heater rods maintained at 95 °C. Water approaches the heater rod bundle in normal direction at a mean velocity of 1.2 m/s. The rods are arranged in-line with longitudinal and transverse pitches of SL = 4 cm and ST = 3 cm. Calculate the number of tube rows NL in the flow direction needed to achieve the indicated temperature rise.

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 7.20P

See similar textbooks

Similar questions

Water at 15°C is to be heated to 65°C by passing it over a bundle of 4-m-long, 1-cm-diameter resistance heater rods maintained at 90°C. Water approaches the heater rod bundle in normal direction at a mean velocity of 0.8 m/s. The rods are arranged in-line with longitudinal and transverse pitches of SL=4 cm and ST=3 cm. Determine the number of tube rows NL in the flow direction needed to achieve the indicated temperature rise. Please, I need the solution from fundamental concepts of how the heat flow behaves in the system. That it be answered with theory of the subject
Water at 15ºC is to be heated to 65ºC by passing it over a bundle of 4-m-long 1-cm-diameter resistance heater rods maintained at 90ºC. Water approaches the heater rod bundle in normal direction at a mean velocity of 0.8 m/s. The rods arc arranged in-line with longitudinal and transverse pitches of SL 4 cm and ST 3 cm. Determine the number of tube rows NL in the flow direction needed to achieve the indicated temperature rise.
Air enters a 10-m-long section of a rectangular duct of cross section 15 cm * 20 cm made of commercial steel at 1 atm and 358C at an average velocity of 7 m/s. Disregarding the entrance effects, determine the fan power needed to overcome the pressure losses in this section of the duct.
What is the physical significant of prandtl number? Question does the value of the prandtl number depend on the type of flow, or the flow geometry? Does the prandtl number of air change with pressure? does it change your temperature?
Determine the Height of a chimney with a static draft of 12 mm if the losses total draft is 4 mm, the ambient air temperature is 35 ° C and theexhaust gas temperature is 450 ° C. The fuel consumption of the boiler is 600 kg / h, the mass of the exhaust gas is 16 kg, also determine the air mass ma, the diameter of the chimney and the velocity of the exhaust gases.
A 20degC water flows to 50cmx60cm flat plate with velocity of 6m/s . The flat plate surface temperature is maintained at 40deg C. The air flows parallel to the 50cm side of the plate. If the kinematic viscosity of water is 78x10-8 m2/s, at what length the flow become turbulent? If the average laminar heat transfer coefficient of water is 7740W/m2 degC, what is the overall heat transfer at the laminar section?
1. Experimental analysis was carried out about turbulent convective heat transfer in trapezoidal cross-sectioned duct.Average Nusselt numbers and Reynolds numbers were determined for each experiment and the following data set have beenobtained from this investigation. Find an engineering correlation between the average Nusselt number and Reynolds numberin the form ofNu = aReb
A 1.2-in-outer-diameter pipe is to span across a river at a 140-ft-wide section while being completely immersed in water. The average flow velocity of the water is 10 ft/s, and its temperature is 70°F. Determine the drag force exerted on the pipe by the river.
Answer completely Show how the Darcy-Weisbach equation can be derived from the Hagen-Poiseuille equation through the introduction of the Reynolds number. What is the friction factor, f, equal to for flow at a laminar condition? What is it equal to in other regimes of flow?
Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.4-m-long tubes inside which the refrigerant is evaporating at -20℃.Air approaches the tube bank in the normal direction at 0℃ and 1 atm with a mean velocity of4 m/s. The tubes are arranged in-line with longitudinal and transverse pitches of SL = ST = 1.5cm. There are 30 rows in the flow direction with 15 tubes in each row. Determine (a) therefrigeration capacity of this system and (b) pressure drop across the tube bank. Evaluate theair properties at an assumed mean temperature of -5℃ and 1 atm. (c) Is this a good assumption?(Answers: (a) 7290 W (b) 639 Pa (c) Yes, this is a good assumption)
Air at 1 atm and 20 C flows in a 2.5-cm-diameter tube. The maximum velocity (m/s) of air to keep the flow laminar is
In an Osborne Reynolds Demonstration experiment, why is it the in laminar flow, the color collected has a color unlike in transitional and turbulent flow where the color of liquid is just transparent?