Antinos said:
I305's wheels are spinning at a much faster rate than Piraten's. I can only imagine what that can do regarding heat generation, but I haven't learned anything about that yet. This is hopefully where Hixee can teach us science!
It's actually rather simple really.
The amount of heat generated in a polymer (or any material for that matter) due to elastic strain is clearly proportional on force, frequency and the material property that governs heat generation under stress (the name of which escapes me at the moment, but lets just call it the stress-induced-heating coefficient). Now lets assume the trains weigh roughly the same, are both pulling a turn with the same force, the wheels are both the same size, and have the same material on their wheels. This means that the only factor affecting the heat generated in the wheel (disregarding all the other external factors) is the frequency of the load. If you imagine drawing a straight line from the axle to the outside edge of the wheel (like a spoke) then that part of the wheel will undergo the compressive force once every time the wheel rotates. The faster the train travels the more often that section of the wheel undergoes the loading, and therefore the faster it heats up.
However, if you make the wheel marginally larger, or slightly alter the material, you could easily change the frequency and/or stress-induced-heating coefficient meaning that the heating of the wheel becomes something you can control relatively easily.*
However, as I said previously, trying to pull a 4G corner at 100mph needs a much bigger corner than a 4G corner at 50mph, and my personal opinion is that the guests then become the limiting factor. Biological factors are a lot harder to change. :lol:
*It is worth noting though, as Hyde244 and jolash said, that the external air temperature and humidity might also impact on this quite heavily, and so in the summer in the Midwest (and most of the time in Texas
) they use the misters to cool the wheels in between circuits. They
could presumably use a much tougher polymer in the summer when the temperatures are very hot, but the rubber on the wheels makes a big difference to ride quality, speed conservation (I've heard people mention them using softer rubber during testing to simulate slow runs) and so a compromise needs to be found. Like has been said many times, there are a lot of factors that affect this sort of thing. I would imagine, however, that the majority of new rides fall within the already well understood material ranges, and so they aren't having to redesign the wheels every time.