Dew point and what it means to you.

alvin l nunley

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Dew point

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This article is about the meteorological dew point. For the petroleum term, see Hydrocarbon dew point.

The dew point is the temperature at which the water vapor in air at constant barometric pressure condenses into liquid water at the same rate at which it evaporates. At temperatures below the dew point, water will leave the air. The condensed water is called dew when it forms on a solid surface.

The dew point is a water-to-air saturation temperature. The dew point is associated with relative humidity. A high relative humidity indicates that the dew point is closer to the current air temperature. Relative humidity of 100% indicates the dew point is equal to the current temperature and that the air is maximally saturated with water. When the moisture content remains constant and temperature increases, relative humidity decreases.[1]
I couldn't find anything on the web about Hydrocarbon dew point.

Isn't the comparison meaningless and vapor pressures are all about the same? I'd have to look into it again. Are you bringing up an old discussion for the sake of invoking an argument, much like the past on Pete's site? If so it's interesting but as I remember you considered it meaningless to bring humidity into the picture. I've just accepted from way back when, humidity is not a factor in engine performance. That is where your heading ain't you Al?

It will be interesting watching you setup others for the debate again, for the sake of arguing to a successful point with them. I'll sure learn from it, up front I use to understand it but don't anymore and I'm just guessing off the top of my head now, because of not using what was learned. Have at it and give us some more to go on about what your proposing. Just throwing out facts to let us hang ourselves on is cool and will lead to some fun, but throw out a little better bait. ... :)
Al, real nice, now that you've described it, how does it affect me? I mean other than making my old bones and joints ache more or less?
Since this is in off-topic - dew point to me means the level of Mtn Dew in my system has either hit a minimum point of survival or the max point before I will have to spend half a day in the restroom
I’ve built a lot of pipes and tested them on the dyno with the KT, lots. I’ve tried many different ideas. Just guessing, but about 98% of them had power curves under my best pipe somewhere in their curves. Some had more high end, some had more low end, but I gave up long ago trying to port an engine to a pipe and a fuel. If you port an engine, “and dyno it”, you might be able to guess a little better, but without a dyno, your chances are very slim that you will come up with something better. Not saying it couldn’t happen.
If you change from gas to alky, and raise the exhaust port, or make the port bigger, (which does pretty much the same thing as raising it. Study area/time) and you think you can do those things to “fit” a pipe and fuel, you’re kidding yourself Now a blind squirrel could still find a nut, but the odds are about the same trying to match an engine to a pipe and a fuel.
Comments compliments criticisms and questions always welcome.
If the data does not support the theory, get a new theory.
It is all about psychometrics and understanding how to make people comfortable, maintain food properly, develop a fridge, freezer or cooler for a certain application...moisture in the air dew point and grains per pound of moisture, wet and dry air.
Oh ya and air conditioning in HVAC as well....
That is what it means to me anyway...
we had -7 dew point in south Missouri last week---very dry air and cold---forecasted dew point is a good indicator of night time temp lows.
Dew point matters to me. In my 1/10 mi. asphalt open wheel racing, I was the only one smart enough to install a remote carb tuner (engine was generally behind driver and inaccessible in my form of kart, like a quarter midget). As the 25 lap feature started, the air was pretty heavy and my car performed average -- it was a midpack car at best, with a cheap but less than optimal design. However, there was a red flag for a flip about 10 laps in. During the 15 minute cleanup, etc., the dewpoint was met and fog rolled in... There was a noticeable change in air density and I adjusted my carb as we fired up and went back in lineup for the start. On the start, I gapped the field by 3/4 of a lap and was able to hold that for my one and only win that season. It was a night race, and I presume the temp was falling though I was busy on track and not viewing a weather station...


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