An air duct heater with an electric heating element in an industrial plant is used. 12 m/s velocity perpendicular to the elements from above to the atmospheric air heater and enters at 27 oC. In the duct heater, each row consists of 3 pipes in the flow direction. It consists of 4 rows. In this air duct heater any two pipes The distance between the centers is 22 mm. Each element in the heater is 12 mm outside diameter, 220 mm length and a uniform surface temperature of 330 oC. Air duct Find the heat transfer rate in the heater and the temperature of the air leaving the heater.

An air duct heater with an electric heating element in an industrial plant is used. 12 m/s velocity perpendicular to the elements from above to the atmospheric air heater and enters at 27 oC. In the duct heater, each row consists of 3 pipes in the flow direction. It consists of 4 rows. In this air duct heater any two pipes The distance between the centers is 22 mm. Each element in the heater is 12 mm outside diameter, 220 mm length and a uniform surface temperature of 330 oC. Air duct Find the heat transfer rate in the heater and the temperature of the air leaving the heater.

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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.16P

See similar textbooks

Similar questions

1. A lead pipe has 2 cm inside diameter, 3 cm outer diameter, length of 130 cm. Liquid water at 4°C flows through the pipe with a bulk velocity of 2.50 km/hr. Air is blown around the outside of the pipe at 20 deg C. The inside wall of the said pipe has a temperature of 8 deg Celsius. Find: a. Overall heat coefficient (U) based on outside surface area b. Prandtl (Pr) and Reynolds (Re) numbers based on classification of flow
n electric generator at a power plant produces energy by passing superheated steam from a high temperature container (reservoir), through a pipe connected to a series of fans, and then into a low temperature reservoir. As the steam passes across the blades of the fans some of the heat energy of the steam is transformed into mechanical energy, which turns the fans which in turn are connected to a generator, which in turn converts the mechanical energy into electrical energy. If the high temperature steam has a temperature of 412.1 K and the low temperature reservoir has a temperature of 105.4 K, what is the Carnot efficiency of this process?
Problem 2: A 5mm x 20 mm rectangle tube houses fully-developed flow of water. The surface temperature is 45°C, and the water enters at 25°C and exits at 35°C. What is the heat transfer.
Consider a pipe on a horizontal plane: based on Bernoulli's equation A. none of the above B. the inlet velocity will be less than the outlet velocity C. the inlet velocity will be greater than the outlet velocity D. the elevation of the inlet will be greater than that of the outlet
Describe the process of internal flow convection heat transfer in an annular tubeconcentric and draw
A thick-walled cylinder tubing of hard rubber having an inside radius of 20mm is being used as temporary cooling coil in a bath. Ice water is flowing rapidly through inside tube and the inside wall temperature is 274.9K. The outside surface temperature is 297.1K. A total of 14.65W must be removed from the bath by cooling coil. How many m of tubing are required?
In a gas manufacturing plants, they presented a horizontal tube in which a gas assumed to be ideal is flowing steadily. It was identified that no heat and work interaction was done. Also, there is a significant changes in the pipe diameter as well as velocity. If in case we select N2 as the flowing gas at 761.67 R at a velocity of 5.6 m/h, Calculate the temperature where the velocity us 180 km/h? Assume cp=7/2 R.
A small-scale Compressed Air Energy Storage (CAES) system uses a rigid tank, whichhas been sized to 1m3. The air storage helps support various fluid power (pneumatics)requirements, but also serves for energy storage (when fully charged).The tank sits in a plant room having a temperature of 25oC at 1 atmosphere (101.325kPa).When delivered new and installed the tank (and the ambient air it contains) is assumedinitially at the same steady state conditions in the plant room. The tank can be filled with(dry) air to a maximum pressure of 300bar. When left in the plant room, the pressurised airtank eventually attains the plant room temperature.You may assume:> Steady state conditions apply> Negligible changes in kinetic and potential energy> Thermal mass of the tank (metal) is negligible Apply the ideal gas equation and calculate the mass of 25oC air (units: kg) in the fullypressurised tank.
24. Water at 80 F is flowing over a flat plate with a velocity of 8 ft/s. The plate is5 ft long. Find and plot the heat transfer coefficient as a function of the platelength.
You, a process design engineer, are tasked to build a powerplant that utilizes 1.5 metric tons of municipal solid wastes (MSW) per hour. In an industrial boiler, MSW is burned to heat and pressurize 1 kg/s of preheated water to high-pressure steam (44 atm, 450 °C). The high-pressure steam, moving at a linear velocity of 70 m/s, is then used to drive a high-pressure turbine. In a heat exchanger, the used steam from the outlet of high-P turbine at an intermediate pressure (10 atm, 250 °C) is used to preheat the water that will be fed to the boiler. This water is pumped from an underground reservoir at a low velocity (1 atm, 25 °C). After preheating the water, the intermediate-pressure steam leaving the heat exchanger is then used to drive a low-pressure turbine. Lastly, the steam from outlet of the low-P turbine leaves at a velocity of 10 m/s (at 1 atm and 100 °C) via an exhaust 10 m above the pump inlet. The industrial boiler is insulated, but due to the high temperatures and the nature…
3. Vertical turbines are to be used for flocculation in a water treatment plant with a design flow rate of 189,270 m³/day. Flocculation is to be designed with two trains and five compartments per train. The total detention time in this process is to be 25 minutes, and the average temperature of the water flowing into the plant is 10°C. The velocity gradient in the first compartment is to be 70 s¹. Make the following design decisions for the first compartment: a) Determine the dimensions of the compartment. b) Determine the diameter of the impeller. c) Determine the water power required. d) Determine the maximum rotational speed. e) Estimate the pumping capacity of the impeller and circulation time in the tank.
48. Water is flowing in a smooth pipe of diameter D. A section of this pipe hav- ing a length of L is heated. Water at the inlet to the heated section has a tempera- ture of Tŋ. Water temperature at the exit of the heated section is Tp. The heated section of the pipe wall is maintained at a constant heat flux so that a constant temperature difference of AT, = T, – T, exists between the wall and the bulk wa- ter temperature. Show that for turbulent flow in the pipe and a specified heated length and pipe diameter, water temperature at the exit of the heated section is given by: 402 0.6 Pr T52 =Tf +0.0876 L AT DO.8 0.2 m