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Cars and Wind Chill

When it comes to starting a cold car, I agree that wind chill has no effect, but when you are trying to heat up a car, the wind will blow off heat as it builds up and make the warm up time take longer.

The wife of the guy that called in said that he should start the car sooner during high wind conditions in order to heat the car up. I think that makes sense.

Wind chill affects things that produce their own heat and a running car does that.

If it effects it, the difference is minimal at best. Your heater uses coolant to heat the air. The coolant runs through passages inside the engine block. The heat has to radiate through the passages before it gets to the surface of the block where wind chill might be a factor.

The wind is also cooling off the passenger compartment where the wife is sitting. That’s the most important part as far as she is concerned.

Sorry - I meant to post this in the “Show” section.

from wikipedia…

“For inanimate objects, the effect of wind chill is to reduce any warmer objects to the ambient temperature more quickly. For most biological organisms, the physiological response is to maintain surface temperature in an acceptable range so as to avoid adverse effects. Thus, the attempt to maintain a given surface temperature in an environment of faster heat loss results in both the perception of colder temperatures and an actual greater heat loss increasing the risk to adverse effects such as frostbite and death.”

“For inanimate objects, the effect of wind chill is to reduce any warmer objects to the ambient temperature more quickly.”

That seems to corroborate my thinking there.

I agree with FoDaddy that any effect is minimal (near non-existent in my book).

There is little air movment under the hood and the coolant in the engine block is not circulating until the engine temp generally reaches around 195 degrees, at which point the thermostat opens. Until then engine heat is building constantly and not even being dispersed through the radiator.

What happens to the wind chill on a cold engine that is allowed to run for a few seconds and then moves the car at 50 MPH; with the thermostat still closed?

I think that if you could put the engine under the same load condition without traveling at 50mph, the passenger compartment would get warm quicker.

Webmaster – please merge this with the same thread (same subject, same title, same OP) elsewhere in this board.

“Wind chill” is simply a way of quantifying the rate at which the environment disspates heat. Yes, it makes a difference. Driving headlong into a strong cold winter wind will cause your engine to take longer to fully warm up (and thus produce heat) than if you were stationary, and possibly significantly longer than if the vehicle were protected from the wind.

When I was in North Dakota we knew that on windy days if we parked facing the wind while on shopping trips the engine would cool down faster, thus when we started the car back up it would take longer to get heat from the systemm.

Adding wind chill does NOT mean the engine will get colder than ambient…only that it will get there faster.

I think the confusion with ‘wind chill’ is that it says ‘it’s 20F, but with the wind chill it feels like -10F’. An object will never get below 20F in that case, regardless of the wind chill. It will cool quicker, or be harder to warm up, but the ‘-10F’ wind chill value is meaningless for a car.

Unless you happen to be trying to warm the engine up and it’s facing into the wind.

Been there, done that, lived in North Dakota.

While the term “wind chill” is designed to convey the effect the wind has on skin at specific temperatures and wind speeds, it in fact is a quantification of the speed the heat is dissipated at. It does in fact have an effect on cars. Cars protected from the wind will warm up faster than cars parked facing the. And on a brisk ND day in -20F ambient with a brisk wind it makes a difference.

I agree with you, however, that the confusion lies in the way it’s expressed. It does make it sound like the object will get colder because of the wind. Perhaps if it were expressed as a disspation rate, say “10 degrees F with the ability to freeze exposed skin in 15 minutes” there’d be less confusion.