PDA

View Full Version : TOP Feed / Bottom Feed in Plate freezers



smpsmp45
05-08-2008, 09:14 AM
Though I am repeating this thread again, I think since I came to know more on this, it ie better to put up that in a new thread.

This concept is important for the Product coolers, but since all the plates ( Circuits) are parallel in case of Plate freezer, this concept is not valid. However for Pump circulation it is important to have nozzles at the entry point into the plates. This point is stated in the ASHRAE itself.

US Iceman
05-08-2008, 02:21 PM
At issue with this topic is the need for uniform refrigerant distribution.

Orifices, while used as a flow restricting device in an attempt to balance the refrigerant flow through each circuit, are very inexpensive. They are however, prone to wear and clogging from debris.

The concept behind the fascination of bottom feed is that the rising gas bubbles help to provide the liquid distribution through the heat exchanger.;)

smpsmp45
05-08-2008, 04:00 PM
Dear Usiceman,

I was after this issue, as I came acorss various points with every supplier & all had no common logic. The Liquid line circuiting to the plates & headers were designed based on their old methodology with no clear cut understadnings of the basic issues. The Orifices was YES & NO issue. Flanged connection was never thought to be odd thing. Hot gas defrosting was never given a thought & similarly all such issues were based on old practices.
But now atleast my curiosity is answered almost 80%

US Iceman
05-08-2008, 07:29 PM
Hot gas defrosting was never given a thought & similarly all such issues were based on old practices.


And now you know how the reasons or lack thereof.:D

Instead of understanding how things work and why, most tend to copy what has been done for years and hope for the best.:rolleyes: