Posted
on November 26, 2016
When
I typed “Carrier” into Google, the first thing that came up was
Carrier Air Conditioning.
And
that's all well and good, because today's birthday boy invented
modern air conditioning!
Born
in New York on this date in 1876, Willis Carrier grew up to be an
engineer. He invented the first air conditioning unit in 1902 and
started Carrier Corporation in 1915. Carrier advertises that it is
still a world leader in HVAC (Heating, Ventilation, and Air
Conditioning).
Of
course, even before Carrier's invention, people had been cooling
their homes and work places since prehistoric times, often using snow
and ice – even storing ice for use during summer. Some people used
shade or moist cloths or reeds hung in windows so that breezes would
bring in cooler, moister air. Even ancient people used water
circulating in pipes inside walls to cool particular rooms, and early
civilizations utilized things such as wind towers and cisterns to
cool the air. Ancient peoples also invented human- or animal-powered
rotary fans to move air around.
But
Carrier's air conditioning unit used electricity to do four important
things:
control
temperature
control
humidity (how much moisture is in the air)
control
air circulation, or movement, and ventilation
cleanse
the air
Basically,
Carrier's invention heated water in order to put more humidity into
the air, and it cooled water in order to take humidity out of the
air.
Carrier
tied together the ideas of absolute humidity, relative humidity, and
dew-point temperature in a document sometimes referred to as the most
important document ever written on HVAC stuff.
Let's
see what these three ideas mean:
Absolute
humidity – a measure of the water vapor in air no matter what the
temperature is, expressed in grams of water per cubic meter of air.
Relative
humidity – a measure of water vapor in the air relative to the
temperature of the air, expressed as a percentage of the total amount
of water vapor that could be held by air at that temperature.
Warm
air can hold a lot more water vapor than can cold air.
Relative
humidity is important because it affects how we experience
temperature. If the air is really moist and 90 degrees, we feel a LOT
hotter and more uncomfortable than if the air is quite dry and 90
degrees.
Dew-point
temperature – when relative humidity reaches 100%, the air is
called “saturated” – which means it is holding as much water
vapor as it can possibly hold at that temperature. Some water vapor
is condensing (forming drops of liquid water) on solid surfaces or
particles, but some drops of water are also evaporating and becoming
water vapor...Because of this steady condensation and evaporation,
the amount of water vapor stays the same.
But
when the temperature drops a smidge (or a lot) below the dew-point
temperature, the water vapor condenses at a higher rate than liquid
water evaporates. And dew begins to form on leaves and blades of
grass and cars and other objects. Or drops of water condense on
particles of dirt or sand in the air, causing the formation of either
fog or clouds, depending on how high the drops are located.
Also
on this date:
Anniversary
of the first European spotting Maui
Plan
ahead:
Check
out my Pinterest boards for:
And
here are my Pinterest boards for:
