Originally Posted by kpoeticg
The theory makes sense, faster the water flows through the loop, the more time it spends in radiators. But research shows that after ~1.5GPM, there's more negatives for the small increases u might see
Actually something to think of and that is flow is not speed... GPM does not tell you how fast the water is moving!!! it is actually suppose to be a measurement of volume, pressure is closer to the speed of the water than GPM. and the higher the volume of water the more heat you can move. but you will reach a point of diminishing returns due to several factors most of all the efficiency of the block to move heat. 1.5 GPM is the ideal point and like you said over this your increases are linearly smaller up to a point and actually then they will decrease, because the water flow is so large it dose not absorb any heat..
and you were right about more time the water spends in the radiator the better. but actually the best way to do this is like a cars thermostat. it regulates the amount of water out of the radiator based on temp this is a regulating valve. but because of size we can not do this in a computer...
we do this with engines regulate the flow into the waterblocks (heat exchangers) and also regulate the flow out of the radiator but to do this we have bypasses and 2 big expansion tanks or reservoirs. we feed the water from the engines and the bypass into a reservoir that is open to air so that the volume can fluctuate and then it goes to the radiators that have big header boxes on them depending on the temp of the water these can hold double the volume of the radiator. so we are able to slow down the flow and not run out of water and with the bypasses we never over pressurize the system.. but there is just not enough space in a PC to do this correctly plus the added maintenance of having a open system.
bored so just some thermodynamics...