Case Design for Liquid Cooling

[Kaldskryke]

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Qcpu = Tdelta * Fh2o / Rblock (since the input and output temp can be considered constant, the heat absorbed by the water in the block is going to be a function of the temp difference between the water and the CPU, the flow rate of the water, and resistance to heat transfer of the block)
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I know I'm new here and all (note my postcount) but how do we know the heat flux is linearly proportional to flow rate?

AFAIK most correlations for heat transfer coefficients for tubes are something more like Nu = 0.023*Re^(0.8)*Pr^(1/3), such as the seider-tate correllation which certainly implies a non-linear relationship between local velocity and heat transfer

Furthermore, when you correctly assume halved volumetric flow through your parallel portions that doesn't mean the local fluid velocity within those portions will be halved, and it's the local fluid velocity that matters, right?

I'd love to be corrected on this because it certainly makes the math simpler