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Unread 10-13-2002, 11:25 PM   #127
Cathar
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Join Date: Sep 2002
Location: Melbourne, Australia
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Quote:
Originally posted by GeminiCool
The point to the rate question is NOT to rehash what was said earlier. I understand the addition thing, I've accepted that. Since the backpressure is a function of velocity, once the 1st reduction is placed in line the velocity reduces significantly. Now when a 2nd restriction is added, the velocity drops of non-linearly. Hence, how close do we need to be? Is saying the 1st drop is a "reasonable" approximation in some situations? I suspect yes.
I've highlighted the error in your reasoning for you. Flow rate (which is more accurately defined as "volume per unit time") is always linear through a system unless we are somehow compressing the liquid, which for the ~1-10PSI that people use in computer water-cooling systems simply is not happening.

The flow rate does not change non-linearly at different restriction points in the system.
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