Recent content by CapriRacer

I think that is fundamentally the problem with measuring the temperature within the air chamber. The probes are usually placed ON something, not suspended in the air.

The only reason I even mentioned convection is because the tire isn't significantly heating the surrounding air because of that convection. Indeed. That was the part that I was missing! And in particular, how that occurred. Interestingly, the way tire load tables are set up would result in...

Indeed!! I'm afraid you're kind of missing the point of the article. It's not about predicting the rise in temperature. It's about getting a feel for the worst case. That 10% pressure rise is something I have a lot of experience with and it even works in Arizona. It's kind of an upper...

A follow up: Thanks to all who helped me understand how water vapor works in pressurized air. This enabled me to write an article: [Unacceptable reference redacted by the Mentors] If you feel inclined, feel free to critique the article. You can leave comments there, or here. Either way...

Baluncore, Thanks for replying. I posted because I wanted to see if I missed something - and as you'll see, I did! As stated, room temperature. Let's assume that is 20°C = 68°F And here's what I left out. A rule of thumb we tire engineers use is that a properly loaded and inflated tire...

I think I've figured out what I needed to figure out. Thanks to all who contributed. Here it is: If I have an air compressor with a full tank at 120 psi, the process of filling that tank resulted in water condensing out, and the air inside that tank is saturated = 100% relative humidity. If...

I see your point. I have to be very careful about which words I choose to describe this. I should know better as I frequently have to deal with such things. What I was trying to point out was that the air within the tire was not at 100% humidity, and that's not always how folks think this...

I don't think that's how this works. The amount of water vapor in saturated air is also a function of pressure. Here's a chart that says that: https://www.engineeringtoolbox.com/water-content-compressed-air-d_1275.html If I assume the air in a compressed air tank is saturated (a pretty good...

Thanks for all the replies. it's going to take me a while to sort through it all. But I still can't get my head around this whole thing. I think part of this confusion is the business of the Ideal Gas Law. If water vapor doesn't follow it, then there should be some test data that shows...

Tire engineer here. I can't seem to get my head around the relative humidity of air inside a pressurized tire. What I'd like to know is if water condenses out of the air inside a tire when it gets cold. I'm trying to figure out the implications of using nitrogen instead of air as an inflation...