Combustion gases from the exhaust of a boiler that come out at 300 °C and 1 atm, are usedto preheat to preheat water in an industrial facility by passing them through a benchof tubes, within which there is a mass flow of liquid water of 6 kg/s. TemperatureThe average wall surface of all pipes is 80°C. Gases enter the bank ofPerpendicular shaped tubes with a velocity of 4.5 m/s. The outer diameter of the tubes isof 2.1 cm, which are arranged in a manner aligned with longitudinal and transverse steps ofSL = ST = 8 cm. There are 16 columns in the direction of flow with eight tubes in each.Whereas exhaust gases have properties very similar to atmospheric air,Calculate the following:a) The average coefficient of heat transfer by convection, in [W/m2K]. (b) The amount of heat transferred per unit length of the tubes, in [W/m] c) The pressure drop through the tube bank, in [kPa]
Combustion gases from the exhaust of a boiler that come out at 300 °C and 1 atm, are used
to preheat to preheat water in an industrial facility by passing them through a bench
of tubes, within which there is a mass flow of liquid water of 6 kg/s. Temperature
The average wall surface of all pipes is 80°C. Gases enter the bank of
Perpendicular shaped tubes with a velocity of 4.5 m/s. The outer diameter of the tubes is
of 2.1 cm, which are arranged in a manner aligned with longitudinal and transverse steps of
SL = ST = 8 cm. There are 16 columns in the direction of flow with eight tubes in each.
Whereas exhaust gases have properties very similar to atmospheric air,
Calculate the following:
a) The average coefficient of heat transfer by convection, in [W/m2K].
(b) The amount of heat transferred per unit length of the tubes, in [W/m]
c) The pressure drop through the tube bank, in [kPa]
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