2 replies to this topic

Considering the following question, would anyone know any other formula besides;

Hn = 0.725[(k^3*rho^2*h*lamda)/N*deltaT*Do*viscosity)]^(1/4)

to solve for the number of tubes (N), or have some other suggestion(s)?

A 1:1 shell & tube heat exchanger is required to cool 10,000 kg/h of light oil from 105°C to 20°C using cooling water which is available at 15°C and leaves at 30°C. The light oil flows inside the tubes and the water is on the shell side.

Calculate the number of tubes for a linear velocity of the oil of 0.8 m/s.

Data
Specification of Heat Exchanger tubes:
Stainless steel, 12.5 mm ID, 16.0 mm OD, 4.0 m length.
Thermal conductivity of stainless steel: 16 W/m °C
Heat transfer coefficient for water on outside tubes: 900 W/ m2 °C
Properties of Oil:
Density: 850 kg/m3
Viscosity: 1.6 x 10-3 Pa.s
Thermal conductivity: 0.15 W/m °C
Specific heat: 1900 J / kg °C

Much appreciated,
Kelly

[SSWBoy]

to solve for the number of tubes (N), or have some other suggestion(s)?

A 1:1 shell & tube heat exchanger is required to cool 10,000 kg/h ... The light oil flows inside the tubes

Calculate the number of tubes for a linear velocity of the oil of 0.8 m/s.

Data
Specification of Heat Exchanger tubes:
Stainless steel, 12.5 mm ID, 16.0 mm OD, 4.0 m length.
Density: 850 kg/m3

Velocity = Volumetric Flow Rate / Flow Area

That should get you on the right path.

Edited by SSWBoy, 19 August 2009 - 01:21 PM.

to solve for the number of tubes (N), or have some other suggestion(s)?

A 1:1 shell & tube heat exchanger is required to cool 10,000 kg/h ... The light oil flows inside the tubes

Calculate the number of tubes for a linear velocity of the oil of 0.8 m/s.

Data
Specification of Heat Exchanger tubes:
Stainless steel, 12.5 mm ID, 16.0 mm OD, 4.0 m length.
Density: 850 kg/m3

Velocity = Volumetric Flow Rate / Flow Area

That should get you on the right path.

thanks for that! i can't believe it was so simple