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Topic: Wind Chill - Pet Peeve

Posted By: valhalla360 on 02/08/11 08:50am

With all the cold weather, disscussions often turn to the effects of windchill. At that point people come on stating comments that innanimate objects do not experience windchill and it is related to evaporation, etc.

As an engineer who understands the principle, this is either wrong or at least misleading. In doing a search online there are multiple definitions of windchill and several sites state there is no universally accepted definition, so I think the principle should hold sway over a specific definition.

In simple terms, when you place a warmer object in colder air, heat will transfer to a layer of air surrounding the object. This layer of warm air will act as a crude form of insulation so that the surface is actually exposed to the slightly warmer air reducing the heat loss. If the air is moving (ie: wind), this layer of warmer air is blown away and a new layer must be heated by taking heat from the object. The faster the wind the thinner the layer that can be formed and the less insulating value this layer of air can create and the faster the object loses heat. This principle happens with all objects alive or not.

This is a more complicated analysis than most people want to hear on the evening weather report. As a result, they developed windchill tables so you could relate a temperature and wind speed combination to what temperature that would be equivilent to if there were no wind. These numbers are calibrated based on a typical human in terms of size, insulative values and normal body temperature.

When you apply it to your dog, water pipes, diesel fuel gelling, heating the rig, etc...the principle holds true (wind will make the object will lose heat faster) but the calibration changes (if the windchill for 20degrees & 20mph winds is 4degrees, you dog may feel 10 degrees mostly because his fur provides better insulation than human skin. His normal body temperature and surface area to volume ratio will also have an impact on the exact value. He will still feel that it is colder than 20 degrees regardless).

When you talk about inannimate objects again the principal holds true but there is another variable. The assumption for the tables you see assumes the object will maintain a consistent temperature. For common usage this makes sense. If a human body drops more than a few degrees, hypothermia and death are likely results, so accounting for the object getting colder isn't worth the trouble. If your diesel fuel tank drops from 75 to 40 degrees it's no big deal (up to a point). As the object gets colder the temperature difference (between the object & the surounding air) gets smaller. That temperature difference has a significant effect on how fast heat is lost. There is a limit when the temperature of the object matches the air temperature, there is no heat loss, so windchill can never cause the actual temperature of an object to go below the actual air temperature.

In fact if the object is colder than the air, a reverse windchill effect comes into play where it can feel warmer. The reason you don't hear about windwarming is because the human body is typically warmer than the air and there is another cooling affect that typically mitigates this waming effect. The other effect is evaporative cooling.

Evaporative cooling also can affect innanimate objects but it requires the surfact of the object to be damp or wet. Human bodies develop the moist surface by sweating. Swamp coolers do this by trickling water onto an evaporation grid. If you are in the desert and they don't mind you wasting water, a small sprinkler spraying the roof of your rig will help cool it (Not the most efficent or effective method though).

How does evaporative cooling work? Temperature is a measure of fast atoms are moving on average(In solids, they are basically vibrating back and forth in place). In a water droplet, they are bouncing around hitting each other and the object the droplet is on. After each hit, some go a little faster, some go a little slower. Unless they are going significantly faster than average, surface tension stops them from flying off into space but occasionally one will get moving fast enough and be pointed in the right direction that it will break thru the surface tension and fly off into the surrounding air. Since only high speed atoms leave, the average of the remaining atoms is lower which corresponds to a lower temperature. This usually isn't a big issue in the winter as evaporation slows down in the cold and your body stops sweating anyway. It works best in low humidity air. In high humidity, almost as many water molecules that are zooming about in the air hit the droplet and they and their high average speed are absorbed, limiting the cooling effect. Wind can speed the evaporative cooling effect especially in dry air. As with the heat a thin layer of air with higher humitity can form around the object with some of those water molecules bouncing back into the droplet. If the wind blows them away, they are less likely to find their way back to the droplet creating a combined wind/evaporation cooling effect.

Bottom line: Wind will cause objects, you, your dog and your rig, to lose heat faster. With inanimate objects there is a limitation that the object will never go below the actual temperature.

If there are any thermodynamics professors out there they can provide the scientific details but I always argued with mine over semantics vs what it actually means.


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Posted By: Twomed on 02/08/11 09:03am

Whatever...when it's that cold you stay warm unless you have to work..or want to play.

From FLA...negligible wind chill this morning, though the palm trees are moving a little bit.


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Posted By: Dutch_12078 on 02/08/11 09:36am

From the National Weather Service:

1. What is wind chill temperature?

A. The wind chill temperature is how cold people and animals feel when outside. Windchill is based on the rate of heat loss from exposed skin caused by wind and cold. As the wind increases, it draws heat from the body, driving down skin temperature and eventually the internal body temperature. Therefore, the wind makes it FEEL much colder. If the temperature is 0 degrees Fahrenheit and the wind is blowing at 15 mph, the wind chill is -19 degrees Fahrenheit. At this wind chill temperature, exposed skin can freeze in 30 minutes.

2. Can wind chill impact my car's radiator or exposed water pipe?

A. The only effect wind chill has on inanimate objects, such as car radiators and water pipes, is to shorten the amount of time for the object to cool. The inanimate object will not cool below the actual air temperature. For example, if the temperature outside is -5 degrees Fahrenheit and the wind chill temperature is -31 degrees Fahrenheit, then your car's radiator will not drop lower than -5 degrees Fahrenheit.

Windchill Terms and Definitions


Dutch
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Posted By: valhalla360 on 02/08/11 09:44am

kaydeejay wrote:

IMHO wind chill is the effect where it feels colder to people than the actual temperature. It is NOT a measure of the rate of cooling (of your rig for example) although there may be a relationship.
The chill factor is simply an attempt to equate temperature plus wind to an equivalent still air temperature as far as we (people) feel it.
An inanimate object will never be colder than ambient temperature, human skin on the other hand, which is subject to moisture evaporation, will feel as if it's colder when there is air movement.
IMHO Wind chill is meaningless if applied to other than people (or animals). Objects will cool until they reach ambient temperature. Hopefully your skin will try to stay warm. It is that effort that creates the feeling of "wind chill".
Failure to do that of course ultimately ends up as Frostbite.
"Heat Index" is the other end of the scale. Again, it means NOTHING to "Things". It is simply a a way of expressing an equivalent temperature in average humidity air for humans to relate to when the actual humidity is sky high.


The reason you feel colder is because your rate of heat loss is greater and your body is struggling to maintain internal temperature. Windchill is a suragate measure of heat loss increases due to wind effects.

It does apply to inanimate objects as they don't always reach ambient temperature. For example, at night your furnace will keep the rig at the temperature you set. Last week we had a night that went down to 5 degrees and was quite windy and we went thru an entire 30lb tank in 24 hours. The next night was even colder down to -2 but the wind had died off and we are still running off that tank 4 days later.

Also your fresh and waste water systems will tend to gain some heat from the rig being warmer and some of that heat. If there is no wind, freezing itsn't likely to be an issue even if the temp goes down to mid to upper 20's. Add a good breeze and you have a much smaller margin for error because of wind chill, yet I see people post that they are concerned and responders say windchill has no effect.


Posted By: kaydeejay on 02/08/11 09:09am

IMHO wind chill is the effect where it feels colder to people than the actual temperature. It is NOT a measure of the rate of cooling (of your rig for example) although there may be a relationship.
The chill factor is simply an attempt to equate temperature plus wind to an equivalent still air temperature as far as we (people) feel it.
An inanimate object will never be colder than ambient temperature, human skin on the other hand, which is subject to moisture evaporation, will feel as if it's colder when there is air movement.
IMHO Wind chill is meaningless if applied to other than people (or animals). Objects will cool until they reach ambient temperature. Hopefully your skin will try to stay warm. It is that effort that creates the feeling of "wind chill".
Failure to do that of course ultimately ends up as Frostbite.
"Heat Index" is the other end of the scale. Again, it means NOTHING to "Things". It is simply a a way of expressing an equivalent temperature in average humidity air for humans to relate to when the actual humidity is sky high.


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Posted By: Calpine on 02/08/11 09:17am

Thank you for taking the time to explain a few simple principles ,,,, however... you have made a few suppositions which is common for the inexperienced layperson. That is: failure to differentiate between heat transfer by convection vs radiation or combination thereof,


Posted By: valhalla360 on 02/08/11 09:47am

Calpine wrote:

Thank you for taking the time to explain a few simple principles ,,,, however... you have made a few suppositions which is common for the inexperienced layperson. That is: failure to differentiate between heat transfer by convection vs radiation or combination thereof,


I understand the difference but it isn't really relevant to the question of if inanimate objects can be affected by windchill.

My theromodymanics professor would agree with you of course?


Posted By: valhalla360 on 02/08/11 09:58am

[quote=Dutch_12078]From the National Weather Service:

2. Can wind chill impact my car's radiator or exposed water pipe?

A. The only effect wind chill has on inanimate objects, such as car radiators and water pipes, is to shorten the amount of time for the object to cool. The inanimate object will not cool below the actual air temperature. For example, if the temperature outside is -5 degrees Fahrenheit and the wind chill temperature is -31 degrees Fahrenheit, then your car's radiator will not drop lower than -5 degrees Fahrenheit.

Quote:



So lets say I keep my car in the garage and warm it up before leaving. And lets say I've let my maintenance go and the antifreeze is only good down to 0 degrees (yeah, it's not a good idea but...). What this says is that my radiator will drop to -5 degrees and thus freeze even though my engine is pumping heat into the radiator?

The weather service response is an oversimplification that ignores many real world examples.


Posted By: weathershak on 02/08/11 10:28am


My son and I made a Wind Chill Factor Simulator for a science project last year and this Hygrometer showed it best. Wind Chill is based on Feel Like temps from animals that sweat.
Using the Hygrometer (wet dry bulb) best simulated this. We used a blower motor. By adding water at the same temperature to the wick on the wet bulb, the temperature stayed the same on both thermometers. As soon as we activated the blower across the thermometers, the wet bulb temp lowered, showing evaporative cooling. We then had a spray bottle with water. People could put thier arm in front of the blower before and after spraying a mist on thier arm to FEEL the difference. It was a fun project.


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Posted By: Dutch_12078 on 02/08/11 10:37am

valhalla360 wrote:

Dutch_12078 wrote:

From the National Weather Service:

2. Can wind chill impact my car's radiator or exposed water pipe?

A. The only effect wind chill has on inanimate objects, such as car radiators and water pipes, is to shorten the amount of time for the object to cool. The inanimate object will not cool below the actual air temperature. For example, if the temperature outside is -5 degrees Fahrenheit and the wind chill temperature is -31 degrees Fahrenheit, then your car's radiator will not drop lower than -5 degrees Fahrenheit.


So lets say I keep my car in the garage and warm it up before leaving. And lets say I've let my maintenance go and the antifreeze is only good down to 0 degrees (yeah, it's not a good idea but...). What this says is that my radiator will drop to -5 degrees and thus freeze even though my engine is pumping heat into the radiator?

The weather service response is an oversimplification that ignores many real world examples.

Obviously, NOAA is discussing a stationary ("inanimate") object with no additional heat source in that example, but you knew that. Wind chill, as used by the weather services, is a measure of a specific wind effect on a specific material, living human skin, under specific conditions. It does not, nor is it intended to, measure all wind effects on all materials. In that context, the wind chill index does not apply to inanimate objects.

Dutch


Posted By: Dutch_12078 on 02/08/11 10:39am

weathershak wrote:


My son and I made a Wind Chill Factor Simulator for a science project last year and this Hygrometer showed it best. Wind Chill is based on Feel Like temps from animals that sweat.
Using the Hygrometer (wet dry bulb) best simulated this. We used a blower motor. By adding water at the same temperature to the wick on the wet bulb, the temperature stayed the same on both thermometers. As soon as we activated the blower across the thermometers, the wet bulb temp lowered, showing evaporative cooling. We then had a spray bottle with water. People could put thier arm in front of the blower before and after spraying a mist on thier arm to FEEL the difference. It was a fun project.

Cool! Really!

Dutch


Posted By: fla-gypsy on 02/08/11 10:50am

Twomed wrote:

Whatever...when it's that cold you stay warm unless you have to work..or want to play.

From FLA...negligible wind chill this morning, though the palm trees are moving a little bit.


+1


This member is not responsible for opinions that are inaccurate due to faulty information provided by the original poster. Use them at your own discretion.

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Posted By: fla-gypsy on 02/08/11 10:51am

Dutch_12078 wrote:

From the National Weather Service:

1. What is wind chill temperature?

A. The wind chill temperature is how cold people and animals feel when outside. Windchill is based on the rate of heat loss from exposed skin caused by wind and cold. As the wind increases, it draws heat from the body, driving down skin temperature and eventually the internal body temperature. Therefore, the wind makes it FEEL much colder. If the temperature is 0 degrees Fahrenheit and the wind is blowing at 15 mph, the wind chill is -19 degrees Fahrenheit. At this wind chill temperature, exposed skin can freeze in 30 minutes.

2. Can wind chill impact my car's radiator or exposed water pipe?

A. The only effect wind chill has on inanimate objects, such as car radiators and water pipes, is to shorten the amount of time for the object to cool. The inanimate object will not cool below the actual air temperature. For example, if the temperature outside is -5 degrees Fahrenheit and the wind chill temperature is -31 degrees Fahrenheit, then your car's radiator will not drop lower than -5 degrees Fahrenheit.

Windchill Terms and Definitions


Makes a lot more sense in fewer words


Posted By: fla-gypsy on 02/08/11 10:51am

weathershak wrote:


My son and I made a Wind Chill Factor Simulator for a science project last year and this Hygrometer showed it best. Wind Chill is based on Feel Like temps from animals that sweat.
Using the Hygrometer (wet dry bulb) best simulated this. We used a blower motor. By adding water at the same temperature to the wick on the wet bulb, the temperature stayed the same on both thermometers. As soon as we activated the blower across the thermometers, the wet bulb temp lowered, showing evaporative cooling. We then had a spray bottle with water. People could put thier arm in front of the blower before and after spraying a mist on thier arm to FEEL the difference. It was a fun project.


very nice project, what is the difference between this and dew point which is measured in a similar way?


Posted By: camperbuds3 on 02/08/11 11:33am

And here I always thought the WIND CHILL temps were just lower numbers the weathermen/women quoted to dramatize the weather conditions.


Posted By: skipnchar on 02/08/11 12:00pm

I bet you feel a LOT warmer now eh? Time to take on that Nitrogen in the tires question next.


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Posted By: Here'n'There on 02/09/11 08:35am

The OP stated "When you talk about inannimate objects again the principal holds true but there is another variable. The assumption for the tables you see assumes the object will maintain a consistent temperature.".

Well OK... dogs try to maintain constant temperature, just as people do - isn't the furnace in my trailer "trying to maintaint a constant temperature"? The furnace produces heated air which flows through the ducts and vents heating the air inside the trailer. The heated air heats the wall, floor, ceiling and windows. As the wind blows harder, the heat in/ near the "skin" of the trailer is lost and is replaced through the function of the furnace heating air inside the trailer which heats the walls etc etc. The harder the wind blows.. the more the skin heat has to be replaced. Different insulation factors that animals, but isn't the effect the same?


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Posted By: valhalla360 on 02/09/11 09:11am

Here'n'There wrote:

The OP stated "When you talk about inannimate objects again the principal holds true but there is another variable. The assumption for the tables you see assumes the object will maintain a consistent temperature.".

Well OK... dogs try to maintain constant temperature, just as people do - isn't the furnace in my trailer "trying to maintaint a constant temperature"? The furnace produces heated air which flows through the ducts and vents heating the air inside the trailer. The heated air heats the wall, floor, ceiling and windows. As the wind blows harder, the heat in/ near the "skin" of the trailer is lost and is replaced through the function of the furnace heating air inside the trailer which heats the walls etc etc. The harder the wind blows.. the more the skin heat has to be replaced. Different insulation factors that animals, but isn't the effect the same?


Exactly but I see responses to concerns about cold weather camping that say wind chill is irrelevant because it is an inanimate object. Assuming there is a heat source trying to keep it warm, windchill is very much a factor.

On a more ammusing note: Not that you should ever do this, but if you have a pet turtle and you set him out on the picknick table in 30 degree weather, will he "feel" a windchill? He's not an inanimate object but he also is unable to regulate his body temperature.


Posted By: valhalla360 on 02/09/11 09:23am

weathershak wrote:


My son and I made a Wind Chill Factor Simulator for a science project last year and this Hygrometer showed it best. Wind Chill is based on Feel Like temps from animals that sweat.
Using the Hygrometer (wet dry bulb) best simulated this. We used a blower motor. By adding water at the same temperature to the wick on the wet bulb, the temperature stayed the same on both thermometers. As soon as we activated the blower across the thermometers, the wet bulb temp lowered, showing evaporative cooling. We then had a spray bottle with water. People could put thier arm in front of the blower before and after spraying a mist on thier arm to FEEL the difference. It was a fun project.


More scientific curiosity than pet peeve on this, but I believe what you are testing is the combined effect of wind chill and evaporative cooling. Each phenominon occurs independently but combined they compound for a more dramatic effect.

I helped my niece do a science project on this also. We set up in the garage with a probe thermometer, a multi speed fan and an aneometer (wind speed measuring device). For a variety of windspeeds and temperatures over a few weeks, she heated a five gallon jug of water to 100 degrees and measured the time it took for them to drop to 95 degrees. The idea being that the rate at which the temperature drops corelates to the rate of heat loss at approximately human body temperature. When you graph the temp vs windspeed and replace the time with the corresponding temp at zero wind speed, it created a graph that was pretty close to the weather service chart.


Posted By: beemerphile1 on 02/10/11 11:45am

Heat transfer and wind chill are not the same thing. Wind chill is the effect of moving air on a living being's skin primarily due to evaporation. Wind chill is also what you experience on a hot day while in the breeze of a fan.

My car parked outside is X degrees no matter what the wind speed is at.

My heated home or RV loses heat due to heat transfer, not wind chill.


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Posted By: TXiceman on 02/11/11 06:33am

V-360, you need to go back and study your thermodynamics and heat transfer.

"Wind chill (often popularly called the wind chill factor) is the felt air temperature on exposed skin due to wind. It measures the effect of wind on air temperature. The wind chill temperature is usually lower than the air temperature, since the air temperature is usually lower than the human body temperature. In contrast, humidity on the skin can result in a higher felt air temperature, and the heat index is used instead."

Wind chill is a felt or perceived temperature due to the cooling effect from the moisture in the skin. A pipe or such will not feel any temperature lower than the ambient temperature.

If it is 33 degF out side and the wind chill is 25 degF, will the pipe with water in it freeze? It doe s not matter if the wind is blowing 5 mph or 100 mph, the pipe will not freeze.

The higher velocity across the pipe will cause the pipe to cool faster due to the increase heat loss or higher heat transfer cofficient. But it will not freeze.

I have spent 40 plus yhears (mechanical engineering and a P.E.) working with thermodynamics and heat trasnfer. Heat transfer and thermodynamics have a lot of concepts that are hard to comprehend by a layman in the field.

Ken


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Posted By: valhalla360 on 02/11/11 07:34am

TXiceman wrote:

V-360, you need to go back and study your thermodynamics and heat transfer.

"Wind chill (often popularly called the wind chill factor) is the felt air temperature on exposed skin due to wind. It measures the effect of wind on air temperature. The wind chill temperature is usually lower than the air temperature, since the air temperature is usually lower than the human body temperature. In contrast, humidity on the skin can result in a higher felt air temperature, and the heat index is used instead."

Wind chill is a felt or perceived temperature due to the cooling effect from the moisture in the skin. A pipe or such will not feel any temperature lower than the ambient temperature.

If it is 33 degF out side and the wind chill is 25 degF, will the pipe with water in it freeze? It doe s not matter if the wind is blowing 5 mph or 100 mph, the pipe will not freeze.

The higher velocity across the pipe will cause the pipe to cool faster due to the increase heat loss or higher heat transfer cofficient. But it will not freeze.

I have spent 40 plus yhears (mechanical engineering and a P.E.) working with thermodynamics and heat trasnfer. Heat transfer and thermodynamics have a lot of concepts that are hard to comprehend by a layman in the field.

Ken


I believe my original explaination detailed that windchill can never drop an object below the actual air temperature (evaporative cooling can), so there is a distinction for inanimate objects, but the faster cooling effect of windchill still applies.

The weather report often talks about frostbite concerns with extreme windchills even though the actual temperatures are not unusually cold (obviously they must be below freezing). Now do you get frostbite because of "feelings" or because of higher heat transfer rates?

Ultimately windchill is a surragate measure of heat transfer rate. So when we talk about things freezing up around an RV, windchill is a good quick and dirty way to assess how much of a concern it is (with the caviot that the actual temp is below freezing).


Posted By: TXiceman on 02/11/11 09:45am

V-360,

Higher heat transfer rates are not wind chill. This is where you are confused.

Ken


Posted By: beemerphile1 on 02/11/11 11:11am

valhalla360 wrote:


Ultimately windchill is a surragate measure of heat transfer rate. So when we talk about things freezing up around an RV, windchill is a good quick and dirty way to assess how much of a concern it is (with the caviot that the actual temp is below freezing).


Well you got the "quick and dirty" part right. Not the "good" part.

By definition "wind Chill" is the effect of moving air on the skin of a living creature. Specifically humans but also relative to many animals.

The "good quick and dirty" is to call it heat transfer, because it does not fit the definition of windchill.

One of my pet peeves is people who claim to be a knowledgeable expert due to being "an engineer who understands the principle" and then spout inaccuracies.


Posted By: TXiceman on 02/11/11 01:22pm

My final Comment is....

The Law of Logical Argument....

Anything is possible if you don't know what you are talking about!

K


Posted By: valhalla360 on 02/19/11 01:19pm

TXiceman wrote:

My final Comment is....

The Law of Logical Argument....

Anything is possible if you don't know what you are talking about!

K


Only to be bettered by the law: If you can't make a logical point, ignore the subject mater and attack the person.

I was talking to one of my co-workers and she actually looked it up and pointed out that yes it is about the rate of heat loss and the NWS FAQ even states this.

She also pointed out that the FAQ actually does state that windchill does affect inanimate objects. She's was also baffled by the use of a radiator as an example of an inanimated object since with a running engine, it will never cool and thus the FAQ is wrong (FYI: just because it is on an official site doesn't mean its right).

1. What is wind chill temperature? back

A. The wind chill temperature is how cold people and animals feel when outside. Windchill is based on the rate of heat loss from exposed skin caused by wind and cold. As the wind increases, it draws heat from the body, driving down skin temperature and eventually the internal body temperature. Therefore, the wind makes it FEEL much colder. If the temperature is 0 degrees Fahrenheit and the wind is blowing at 15 mph, the wind chill is -19 degrees Fahrenheit. At this wind chill temperature, exposed skin can freeze in 30 minutes.

2. Can wind chill impact my car's radiator or exposed water pipe? back

A. The only effect wind chill has on inanimate objects, such as car radiators and water pipes, is to shorten the amount of time for the object to cool. The inanimate object will not cool below the actual air temperature. For example, if the temperature outside is -5 degrees Fahrenheit and the wind chill temperature is -31 degrees Fahrenheit, then your car's radiator will not drop lower than -5 degrees Fahrenheit.

8. Windchill factor vs. wind chill temperature.

A. These terms are almost the same. The wind chill factor describes what happens to a body when it is cold and windy outside. As wind increases, heat is carried away from the body at a faster rate, driving down both skin temperature (which can cause frostbite) and eventually the internal body temperature (which can kill).


Posted By: beemerphile1 on 02/19/11 06:32pm

valhalla360 wrote:



...I was talking to one of my co-workers and she actually looked it up and pointed out that yes it is about the rate of heat loss and the NWS FAQ even states this...


Well if someone's co-worker saw it on an unknown and un-linked website then it must be true.

According to this NWS website, Windchill is the effect of heat transfer on the human body.
http://www.nws.noaa.gov/om/windchill/



Quote:

The NWS Windchill Temperature (WCT) index uses advances in science, technology, and computer modeling to provide an accurate, understandable, and useful formula for calculating the dangers from winter winds and freezing temperatures. The index:

* Calculates wind speed at an average height of five feet, typical height of an adult human face, based on readings from the national standard height of 33 feet, typical height of an anemometer
* Is based on a human face model
* Incorporates heat transfer theory, heat loss from the body to its surroundings, during cold and breezy/windy days
* Lowers the calm wind threshold to 3 mph
* Uses a consistent standard for skin tissue resistance
* Assumes no impact from the sun (i.e., clear night sky).


I don't see anything in there about inanimate objects, and I provided a actual link to the site I quoted.


Posted By: valhalla360 on 02/20/11 06:36am

Sorry for not providing the link to the FAQ that was quoted earlier by others(see below). The co-worker comment was only because that is what got me going on the subject again.

The fact still remains (and your comments appear to agree?) that it is all about heat transfer rates which will increase for both animate and inanimate objects.

http://www.weather.gov/om/windchill/windchillglossary.shtml

* This post was edited 02/20/11 08:18am by an administrator/moderator *


Posted By: beemerphile1 on 02/20/11 08:41am

I apologize if I sounded like I agree with you. I do not.

Here I quote what I stated earlier:
beemerphile1 wrote:

Heat transfer and wind chill are not the same thing. Wind chill is the effect of moving air on a living being's skin primarily due to evaporation. Wind chill is also what you experience on a hot day while in the breeze of a fan.

My car parked outside is X degrees no matter what the wind speed is at.

My heated home or RV loses heat due to heat transfer, not wind chill.


To quote from the first answer in your own link:
Quote:

1. What is wind chill temperature?
A. The wind chill temperature is how cold people and animals feel when outside...


Key words are people and animals. I don't see the word inanimate objects.

I won't comment further. To me this thread is dead and not worth continuing.


Posted By: lesmore49 on 02/20/11 01:30pm

It was 29 below this am, with a windchill of 35 below...darn near froze my

I can hardly wait till it's 70 above with a wind chill of 65 +...I notice that's warmer....I'm not evaporating as fast, I suppose.


lesmore49


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