Freeze Dryer Condenser Surface Area Versus Shelf Area

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Proper design of any sublimation/condensing system (a.k.a. freeze dryer) must take into consideration sizing of two of its most basic components: heat transfer shelves and the condensing surfaces. Sizing of the shelf area is quite basic in that it must simply be of sufficient area to contain all of the product to be dried in one cycle. The condensing surface area, however, is a different case. In some circles, a strict one to one ratio is adhered to, that is, the condensing area is held equal to the shelf area. However, as shall be shown below, further consideration of the problem shows that adhering to a strict ratio is not the proper method for the sizing of a condenser. These considerations are as follows.

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