4 replies to this topic

[ProcessEng_12]

Hi
I want to calculate volume of kettle type reboiler's shell with varying level % change. The shell is comprised of three parts: 1. Cylindrical shell, 2. Hemispherical/ elliptical head 3.trapezoidal part.
I am struggling with the trapezoidal part.
Please help me with that

Edited by ProcessEng_12, 09 November 2021 - 01:36 PM.

[FRBChemE]

The Trapezoidal section can be computed as the volume of a cone. The volume at various horizontal levels may be a bit harder to figure out.

[Bobby Strain]

Why do you want to undertake such an exercise? Kettles usually have a fixed weir to assure the tube bundle is always submerged.

 

Bobby

Edited by Bobby Strain, 09 November 2021 - 11:18 PM.

[breizh]

Hi,

What is the purpose of the exercise , kettle reboilers are equipped with weir to keep constant the volume of liquid to cover the bundle  ?

 

If it's a new unit , I will use water and simple meter used for tap water to evaluate the volume function of the liquid height .

It could be part of water test similar to what you do for tanks.

my view.

Breizh 

[Pilesar]

Liquid level in a kettle can be very uneven, especially if there is high heat flux. The liquid level indication of a kettle exchanger is often only measuring the region of the shell downstream of the weir. Liquid volume upstream of the weir includes the space up to the weir height plus additional liquid level required to crest the weir. There may be liquid also in a foaming layer at the top as well as some liquid entrained in the disengaging space. Subtract the volume of the bundle to estimate the overall liquid volume upstream of the weir. Add in the variable liquid volume downstream of the weir required for liquid holdup including the liquid found in the dished head space.

  If your question just concerns mensuration, the conical section of a conventional kettle is usually 30 degrees from the horizontal. The height of the cone section is the difference between the shell inside diameter and the port inside diameter so the length of that section would be the difference in the shell and port diameters divided by Tan30.