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Old 10-05-2012, 09:23 AM   #75
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Originally Posted by WDE46 View Post
Thanks for explaining basic algebra to me like I'm a 5 year old.

No we have 1 unknown, and that is P2 in my equation. We have P1,T1, and T2 through the use of our coolant sensors and barometric pressure. There is also the assumption of constant volume, which may or may not be poor, depending on how much the water actually expands. This is where you use steam tables to solve for everything (empirically determined numbers with interpolation). I'm not writing a paper here, I thought I could skip that part of showing my work...
Why do you need two sets of P and T? One set is not only redundant, but will also bias the results. For example, barometric pressure P1 is not the same everywhere, and what value of T1 you choose? It is arbitrary.
Originally Posted by WDE46 View Post

I am one.

You're clearly a smart guy, and we both know what the other is talking about. Let's stop arguing semantics. I also see that we both enjoy math which is hilarious. I always find myself making things a bit more complex than they are, just because I want to use my math.
That's what I am trying to convey to you. The situation is simpler than you think it is. You only need a single temperature value to calculate the pressure in this case.

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