CAD Exploded View

Exploded View of Desal Component, showing parts

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Log Wed 28 September 2011

Accomplished:
-3D AutoCAD Drawing


Goals:
-Call mentor
-AutoCAD exploded view

Log Mon 26 September 2011

Accomplished:
-added more visuals to Background Information and design briefs
-added more information re: previous solutions to Background Information

Goals:
-call mentor
-AutoCAD 3-D Drawing
-Obtain Materials and Supplies for Scale Model

Log Fri 23 September 2011

Accomplished:
-Emailed mentor, set up a phone call
-Confirmed attendance at Solar Panel Workshop on 6 October 2011
-Final Materials List
-Final Supplies List

Goals:
-Call mentor
-Obtain materials and supplies for Scale Model

Final Supplies List for Scale Model

-Glue
-Tape (Duct and Scotch)
-Scissors or Exacto Knife
-Black Spray Paint

Final Materials List for Scale Model

For Reservoirs:
-Home Depot Bucket
     

For Tubing, spout, etc:
-PVC tubing
-Bulkhead fitting

For Desalination Cone:
- thin black plastic sheet (approx. 25 square cm)

Materials Brainstorming: Scale Model

 For the reservoirs:
-Foamcore
-aluminum cans
-plastic tubing
-buckets
-cardboard

For the Tubing:
-thread (it doesn't have to work etc)
-plastic straws
-PVC
-k'nex

For the Desal Cone
-saran wrap
-tinfoil
-thin black plastic

Log Wed 21 September 2011

Accomplished:
-Finished isometric CAD drawing
-Emailed mentor with blog URL and questions
-Finished Design Matrix for Rationale Report
-Finalized Calendar post

Goals:
-Get Face-to-Face with mentor
-Finalize Rationale Report - spelling, grammar, etc
-Develop Materials list for scale model

Isometric Drawing of Desalination Component (CAD)

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Final Solution Rationale Report

  Re-introduction of Solutions:

Alternate Solution 1 features a desalination cone followed by 9 chambers of thermal distillation, powered by an array of solar panels on the "roof". The water travels in a circular path from chamber to chamber and eventually drips into a collection basin attached to the bottom of the unit, where UV lights can sanitize it. Water is dispensed through a faucet on the side, perhaps with an attached pitcher.

All of the moving parts are consolidated into one box,  which is good for streamlining the process and for improving aesthetics. The nine chambers of desalination are what is recommended by large-scale facilities, but at our price point, one has to wonder if we can really afford to power all of those

Alternate Solution 2 is basically the same as AS1, except that its storage receptacle is separate from the unit itself, which allows for an indoor storage unit and outdoor desalination unit, connected by a hose. This would make it easier for families to gain access to their fresh water.

Alternate Solution 3 utilized the property of parabolas to focus light at a point to speed up the solar desalination of a desalination cone. A parabola of mirrors would be constructed around an elevated desalination cone, and the rapidly evaporating water would be carried by gravity to a storage receptacle. This configuration had very little power needs but would be difficult to assemble perfectly for maximum efficiency.

Alternate Solution 4 also uses the sun as the direct power for the distillation of the seawater. The traditional desalination cone is placed on top of a chambered receptacle, which holds the saltwater (to be evaporated) in an inner chamber, and after it evaporates and condenses, it is allowed to run down the sides of the cone into an outer chamber, and thence through a tube into a storage unit where UV light awaits it. The water in the outer chamber is protected from further evaporation by two slanted flaps that allow water to flow past, but block almost all light. The unit would be placed outside and elevated, so that gravity could carry the freshwater down to a storage unit inside the house. The UV lights are the only things that need power.

Selection
  Our group decided to use Alternate Solution 4 for our final product, based on analysis of several factors, including power availability and uptake. This solution drastically decreases the energy used by relying solely on solar distillation, rather than boiling the water many times in many different chambers (AS 1 and 2). The cylindrical, cone-topped shape is compact, with few moving parts for easy installation and maintenance. Also helping with ease of user interface is the screw-off top, making the inside easy to clean of salt residue.

        Since the sun directly desalinates the water from the inner reservoir and the desalination unit will be elevating, utilizing gravity to transfer the freshwater to the storage unit inside, the solar panels will only be needed to power the UV lights that disinfect the water in the storage reservoir. This drastically reduces the number of solar panels needed, which will lower our manufacturing costs and installation difficulty.

    None of our alternate solutions could produce 40 litres solo, so no matter which design we chose, multiple units would need to be assigned to each household. With AS 4, however, the construction of multiple units would be easier, cheaper, and overall more feasible than with the other solutions, which involved many small chambers and moving parts. With AS 4, each small barrel can be hooked up to the same indoor reservoir, and families would not have to worry about a multitude of heat plates or membrane systems outside their house. Overall, this solution is markedly simpler and more efficient, not only for us, the manufacturer, but for the eventual customer.
To see more imagery of our final solution, (WITH EDITS), click here, HERE or here. For an explanation of the edits you see in the additional drawings, click here - 

Below is the Design Matrix used to choose the Final Solution.
Though one of our top specifications is "desalinates and purifies water", all of the Alternate Solutions would accomplish that task, so that specification was divided into Volume and Speed of desalination (Columns 1 and 2). Thus, we can better see which design would be the most practical. 

	Productive (Volume)	Efficient (Speed)	Streamlined (Aesthetics)	Sturdy  (Materials)
AS1	2 Once the center cone is full, volume is set at that small number, unless it is refilled.	3 Though the water might boil faster, it would still have to travel through 9 chambers.	3 With all moving parts hidden inside the box, the machine looks quite streamlined and aesthetically pleasing, barring the sharp corners and/or size	2 Boxes are quite sturdy, but since everything is outside, it is more susceptible to breakage.
AS2	2 Once the center cone is full, volume is set at that small number, unless it is refilled.	2 Though the water might boil faster, it would still have to travel through 9 chambers and a tube.	2 Each component of the device is streamlined, but spreading it from outside to inside makes it less aesthetically pleasing, involves more tubing and such.	3 Keeping the main storage unit inside reduces risk. The box left outside is still quite sturdy.
AS3	1 Only a thin layer of water can be added at a time.	1 With only the sun for heat, water would evaporate slowly, and still have to travel through the tube	1 This requires a lot of outside land area for the mirror array, and the desal component looks like a demented birdbath. No one wants this in their yard.	1  That one pillar on which the desal component stands is absurd. Also, the mirrors will constantly break or go out of alignment.
AS4	4 The double-walled cylinder shape offers high input volume.	4 Heat is more focused, so evaporation will be faster, and there is only one chamber to deal with.	4 Two streamlined cylinders are highly aesthetically pleasing. Maintenance should be a breeze. Highly desirable.	4 Cylinders are good at being outside (ie garbage cans, flagpoles, etc). If weighted properly, this should be perfect.

Total: AS1=9, AS2=10, AS3=4, AS4=16

CAD Orthographic Drawing

Front

Intake Detail

Catchment and Outflow detail

Side

Top

IMPORTANT DESIGN EDIT

After a meeting with mentor Dr. Robert Miskewitz, GMG made the decision to invert the desalination cone on top of her component of the desalination unit. This decision was made due to the principles of condensation and gravity, wherein condensed water is more likely to cohere (and thus form droplets) if it is allowed to run to a singular point, rather than forced to disperse along a circle. With the original cone design, the water droplets would be forced farther away from one another as they condensed, making it difficult for droplets to form. If the cone is inverted and allowed to come to a point, all the water will be forced to that one point and droplets will form much easier and faster, increasing device efficiency. Overall, this edit will have a beneficial effect on the productivity and speed of the desalination process.

Calendar Schedules MP1

Log Mon 19 Sept 2011

 Accomplished Today:
-Scanned all Alternate Solutions and Brainstorming (hand drawings)
-Organised AS and Brainstorming posts with captions, descriptions, and rationales
-Finished CAD Orthographic of Final Solution
-Uploaded Calendar Templates to Blog


Goals for Next Checkpoint:
-Finish Calendar post - descriptions, etc
-Continue CAD Isometric of Final Solution
-Finalize Rationale Report for Final Solution - make design matrix!