Wind Meter

7/31/2019 Wind Meter

1/6

WIND METER:

HISORY OF WIND METER:

The history of wind power shows a general evolution from the use of

simple, light devices driven by aerodynamic drag forces; to heavy,

material-intensive drag devices; to the increased use of light, material-

efficient aerodynamic lift devices in the modern era. But it shouldn't be

imagined that aerodynamic lift (the force that makes airplanes fly) is a

modern concept that was unknown to the ancients. The earliest known

use of wind power, of course, is the sail boat, and this technology had

an important impact on the later development of sail-type windmills.

Ancient sailors understood lift and used it every day, even though they

didn't have the physics to explain how or why it worked

The first windmills were developed to automate the tasks of grain-

grinding and water-pumping and the earliest-known design is the

vertical axis system developed in Persia about 500-900 A.D. The first

use was apparently water pumping, but the exact method of water

transport is not known because no drawings or designs -- only verbal

accounts -- are available. The first known documented design is also of

a Persian windmill, this one with vertical sails made of bundles of reeds

or wood which were attached to the central vertical shaft by horizontal

struts (see Figure 1a). A 19th Century American approximation of this

panemone device is shown at the left (Figure 1b).

Grain grinding was the first documented wind mill application and

was very straightforward. The grinding stone was affixed to the same

vertical shaft. The mill machinery was commonly enclosed in a building,


2/6

which also featured a wall or shield to block the incoming wind from

slowing the side of the drag-type rotor that advanced toward the wind.

Vertical-axis windmills were also used in China, which is often claimed

as their birthplace. While the belief that the windmill was invented in

China more than 2000 years ago is widespread and may be accurate,

the earliest actual documentation of a Chinese windmill was in 1219

A.D. by the Chinese statesman Yehlu Chhu-Tshai. Here also, the primary

applications were apparently grain grinding and water pumping.

One of the most scenic and successful applications of windpower (and

one that still exists), is the extensive use of water pumping machines onthe island of Crete. Here, literally hundreds of sail-rotor windmills pump

water for crops and livestock.

Figure 1a. Maximum efficiency

of a "drag" device is obtained

when the collector is pushed

away from the wind, as is a

simple, drag-type sail boat.


3/6

Kestrel 3000 Pocket Wind Meter:

NK was the first to provide accurate relative humiditymeasurements from a hand-held weather meter, and the Kestrel 3000

features two patents on its humidity measuring sensors. A testament to

the 3000s accuracy: its become practically required equipment for

wildland firefightersusers whose lives literally depend on the

accurate weather data their Kestrel 3000 provides.

From the Kestrel 3000s accurate relative humidity readings, it also

calculates the dewpointheat stress indeximportant information to

know when working or playing outdoors in hot and humid conditions.

and

Kestrel Wind Meters are used by NFL trainers to determine how

frequently the athletes need to hydrate, and when the conditions are

unhealthy for strenuous exercise.


4/6


5/6

SPECIFICATIONS AND LIMITATIONS:

Kestrel 3000 Measures

Current Wind Speed

Maximum Wind Gust

Average Wind Speed

Air, Water & Snow Temperature

Wind Chill

Relative Humidity

Heat Stress Index

Dewpoint

FEATURES:Protective cover with sure-grip overmolding

Data hold function

Large easy-to-read display with backlight

Waterproof and floats

Humidity sensor can be recalibrated in the field with our Relative

Humidity Calibration Kit.

User-replaceable impeller

External temperature sensor


6/6

Patented Quick-Response RH Sensor

All instruments and accessories are completely assembled in the USA

5-year warranty

Kestrel 3000 Includes

A slip-on protective cover

Neck lanyard

CR2032 coin cell battery (Average life 300 hours)

Kestrel Certificate of Conformity

APPLICATIONS:

Typical applications

1.Agriculture - checking conditions prior to crop spraying or burning2.Aviation - gliders, para-gliders, micro-lights, parachutists and

ballooning3.Construction - site safety, working conditions, working at height in

cranes or access vehicles

4.Education - air flow experiments, environmental studies, outdoorsports

5.Heating and ventilation - air flow through fans, checking conditionof filters

6. Industry - air flow measurements, pollution control7.Science - aerodynamics, environmental science and meteorology8.Fire fighters - checking fire spreading hazard9.Outdoor activities - sailors, walkers, model boats/air craft, kite

flyers, archery, shooting, fishing, golf & athletics

Wind Meter

Documents

Transcript of Wind Meter