Question

1)Saturated steam at 1.20bar (absolute)is condensed on the outside ofahorizontal steel pipe with an inside and outside diameter of 0.620 inches and 0.750 inches, respectively. Cooling water enters the tubes at 60.0°F and leaves at 75.0°F at a velocity of 6.00ft/s. (HINT: You may assume laminar condensate flow.You many also assume that the mean bulk temperature of the cooling water is equal to the wall temperature on the outside of the pipe, T".You may also neglect the viscosity correction in your calculations.)a)What are the inside

Answer 1

Answer:

hi = 7026.8  W/m^2.k

Explanation:

Given data :

pressure of saturated steam = 1.2 bar

Horizontal steel pipe : inside diameter = 0.620 , outside diameter = 0.750 inches

temperature of water at entry = 60°F

temperature of water at exit = 75°F

velocity of water = 6 ft/s

Calculate the Inside convective heat transfer coefficient ( hi )

mean temperature ( Tm ) = 60 + 75 / 2 = 67.5°F ≈ 292.877 K ≈ 19.727°C

next : find the properties of water at this temperature ( 19.727°C )

thermal conductivity = 0.598  w/m.k

density = 1000 kg/m^3

specific heat ( Cp ) = 4.18 KJ/kg.k

viscosity = 0.001 pa.s

velocity of water = 6 ft/s ≈ 1.8288 m/s

∴ Re ( Reynolds number ) = 28712.16

and Prandtl number ( Pr ) = (4180 * 0.001) / 0.598  = 6.989

finally to determine the inside convective heat transfer coefficient we will apply the Dittos - Bolter equation

hi = 7026.8 w/m^2.k

attached below is the remaining solution