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Hi, I'm Rick Gillan.
Welcome back to Coolerado.
In this video we will show you how we were able to achieve
the 100 Fahrenheit temperature drop
that you witnessed in the Introduction video.
We will also describe the basics of how we are able to cool
below the wet bulb temperature of incoming air.
Lets begin by taking a closer look at direct evaporative cooling,
which is commonly referred to as swamp cooling.
Swamp cooling as been around for thousands of years.
You simply blow air over a wetted surface,
so that the air evaporates water off the surface
and into the air stream.
Common residental swamp coolers blow air
through shredded aspen trees
contained in a mesh and wetted by continously pouring water from above.
Commercial and some residental swamp coolers
use a corrugated cardboard system
instead of Aspen trees, which works in a similar fashion.
When water evaporates into air,
it changes state from a liquid to a vapor
and it absorbs heat from the air surrounding it.
The total energy within the air stays the same.
But, the air feels cooler because the water molecule
has absorbed and hidden the heat within the air.
Again, the total heat energy in the air stays the same.
Air can only hold so much water,
The temperature limitation for adding water to air
is called the wet bulb temperature.
Aspen pad swamp coolers can reach to about 70 percent
of the wet bulb temperature from the their starting point.
Corrugated cardboard type swamp coolers are better at swamping the air
and they can reach to about 90 percent of the wet bulb temperature.
These types of mechanisms
are called direct evaporative coolers
because they add moisture directly to the air that enters the building.
Direct evaporative cooling
is a adiabatic cooling,
which means no heat energy is removed from the air stream.
The heat is simply hidden in the water molecule, in the air.
Indirect evaporative coolers,
use the principles of evaporation,
but it does not add any moisture to the air entering the building.
An indirect evaporative cooler utilizes a heat exchanger.
A common example of a heat exchanger
is the radiator in a car.
The hot liquid in your car's radiator
transfers heat to the air outside with out the air from the outside getting in
or the hot liquid from the inside getting out.
The same heat exchange principle is true for an indirect evaporative cooler.
This is a plastic coated piece of paper.
It is paper on one side, coated with a thin layer of plastic on the other.
If you wet one side of this paper with water, and blow air past it,
the water evaporates from the paper and cools the plastic.
In this process you are exchanging mass in the form of water to vapor in the air.
The plastic is the heat exchanger,
and it in turn will cool and pull heat away from the air on the other side.
This is similar to how your body, skin, and
perspiration work together to cool your body.
Indirect Evaporative cooling is called sensible cooling
and heat energy is removed from the product air stream.
Now, imagine mounting this plastic coated paper
in the middle of a long insulated tube,
much longer than you have here.
Then image wetting the paper side with water
and blowing air through the tube.
The air on the wet side
is going to absorb moisture until it reaches the wet bulb temperature.
That process will pull heat away from the plastic,
which will in turn pull heat away from the adjacent air stream.
When you come out the other end of this long imaginary tube,
the air on the plastic side will be dry
and it will be close to the wet bulb temperature
of the entering air stream.
This is indirect evaporatove cooling.
It is both a heat and a mass exchange process.
So, in theory, the conditioned air you get at the end of this long pipe
is going to be about half the quantity of the air you started with,
and it will be cooled to the wet bulb temperature
without adding any moisture.
But, we know that Coolerado Coolers
can cool below the wet bulb temperature
and our theoretical limitation
is cooling towards the dew point temperature of air.
Lets go back to your theoretical long tube heat and mass exchanger.
When the air comes out of the dry side of the pipe,
it will be cooler and its wet bulb temperature will have been lowered.
You'll throw away the humid air from the wet side to the atmosphere.
Then, you'll take the dry side air stream,
and you run that down, yet another one of your heat and mass exchange pipes.
After throwing the humid air away again,
you'll end up with 1/4 the amount of air you started with
and this air will be cooled below the original wet bulb temperature.
If you keep repeating this process,
you can theoretically approach the dew point temperature
of the original air stream.
However, you would only end up with a small fraction
of the quantity of air that you originally started with.
In addition, you'd lose a bunch of energy to friction
and pressure drop losses, so the process would be of little value.
The Coolerado Coolers have a small pressure drop lose,
less than one inch column of water,
we only throw away about 50 percent of the incoming air stream,
and we can cool toward the dew point temperature of the incoming air.
With this knowledge you can begin to understand
if you are a genius of the Maisotsenko.
Lets take a look at the Coolerado Heat and Mass exchangers
that we use in our demonstration cooler.
The plate heat exchangers are made from the same plastic coated paper
that I showed you earlier.
We attached guides to these plates
to create channels for air to flow through.
We than assemble these plates together to create a heat and mass exchanger.
All of the air being pushed by the fan,
enters this end of the heat and mass exchanger
and begins the flow in this direction.
The air that enters the top half of the channels,
travels straight through to the other end
and only comes into contact with the plastic side
of the heat exchanger along the way.
When we look at the product end of the heat and mass exchanger,
we can see that the lower half of the channels have been blocked.
These channels are our working air streams.
The air that enters the lower half is the working air stream.
All the working air initially enters the dry channels.
Within the first inch, the first 1/13th of air is fractioned off,
and goes into an adjacent wet channel.
The wet channel is wet
because it is sitting in a reservoir of water at the bottom,
and wicks the water up along the length of the wet plate.
The wet channel is perpendicular to the dry channel
and exits out the top of the heat exchanger.
As the first 1/13th of air
travels in cross loads in both the working and product air
it takes heat away from the dry channels from the plastic heat exchanger.
This same process occurs another 12 times,
incrementally cooling both the product and working air streams
as the air travels down the heat and mass exchanger.
This is the heart of the Maisotsenko Cycle.
Incrementally cooling both the product and working air streams
through heat exchange, while incrementally fractioning off some air
to aid and lower temperature, vaporization, and mass transfer.
In short, this elegantly ingenious and simple process
is how we achieve temperature drops
that have never been seen before.
This huge temperature drop is created with a little water
and the power of a fan.
In fact, if you could harness the wind through this little machine,
you would not need any power at all.
We invite you to view the next video
titled "Humidity and Coolerado Cooling."
We'll examine what regions of the world and projects
are good fit for Coolerado Coolers!