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Design Plan


Overall System Design


The system will consists of three units, set in parallel. The dimension of each unit is .5m x .5m x 1.3m; designed to handle a flow rate of
17m/min.Each individual unit will consist of 38 cooling disks, inner-locking in three rows. Each row of rotating disk will be connected externally
with a swiveling disconnect. The swiveling of the disconnect is to account for the rotation of the disk. There will be force across the disk using
a fan. Cooling will be provided by circulating water through the disks at a constant 4.5C. Collected heat will be removed from the water by the use
of a secondary coolant, i.e. chiller.


Water Chiller


The water chiller will re-chill the water returning fron each unit. All the supply water will pass the coil, where a secondary coolant will
chill the water. The secondary unit will be chilled to 4.5C and circulated by a compressor. The water will then be circulated out of the chiller
by the use of the primary and secondary pumps, which will operate in parallel.


Cooling Disks


Environmental cooling and dehumidification will be provided by forcing air across a series of cooling disks. A coolant will be circulating
within the disks to extract the collected heat. The disks will be constructed out of a material that is corrosion resistant, provides a large
heat transfer rate, and has a large static friction coefficient. This is to prevent the loss of condensate from the disk; we have determined
the maximum rotational speed to be 1.2 rpm. The disks will be in constant contact with the wiper assembly to remove the collected condensate
from the disk. Each unit will have an individual belt driven motor with the three axles of the disks being driven. The approximate dimensions
of the disk are:
Radius - .2m
Thickness - .015m
Surface Area - .26m
A hydrophilic coating will be applied to the surface of each disk to ensure even distribution of condensate.


Wiper Assembly and Collection Basin


The wiper assembly is used to wipe the condensate from the cooling disks. It will be stationary, and located along the radial axes of the disks.
The wiper assembly will contact the disks, effectively scraping off the condensate as the cooling disks rotate. The wipers will be constructed
out of a material that reduces the friction between the cooling disks and the wiper assembly. Also located on the wipers will be a material
(such as silver) that will aid in the sterilization of the collected condensate. The wipers and sterilization material will be easily replaced as
part of scheduled maintenance for the unit. Located within the wiper assembly is a collection basin used to store the fluid collected until it is
extracted.


Condensate Extraction System


The water extraction system will remove collected water from the collection basin and supply it to a potable water system, while ensuring that
gas is not mixed within the condensate. Within the collection basin are water level sensors. When the condensate in the basin reaches a certain
level, the water extraction system will be activated, removing the water from the basin. Once activated, it will continue to remove water until
a low level sensor is activated. The water extraction system will create suction to remove the collected condensate in the same fashion that a
syringe creates suction to draw fluid. The suction device will consist of a container and a plunger. The plunger is drawn backwards increasing
the volume of the container creating suction. When the container is close to becoming full, the plunger will then be depressed forcing the
collected water out and into a preexisting potable water system.


Sterilization System



To prevent bio-fouling, along with the sterilization material located on the wiper assembly, the cooling disks will be constantly illuminated
with ultraviolet light. Several ultraviolet lamps will not only provide sterilization for the disks, but also reduce the amount of living
contaminate in the air circulating through the cooled environment. Ultraviolet lamps provide sterilization because of their ability to penetrate
the membrane and cell wall of microorganism, thereby destroying the inner material and completing sterilization. Variants of sterilization with
silver include either applying a strip onto the wipers or coating the basin with silver. Silver absorbs the oxygen in the immediate vicinity,
thereby starving single celled organisms of the oxygen needed for survival.


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