RE:Best way to flush coolant system? |
Subject: RE:Best way to flush coolant system? by CentralCoaster on 2008/1/11 23:03:27 Increasing flow helps, but you quickly hit the point of diminishing returns. Cooling capacity of the radiator is determined by LMTD. Log mean temperature difference. Basically, the average temperature difference between the air and the coolant. Moving both through there infinitely fast means the coolant and air temps don't approach one another. Moving them at a snails pace allows them to equalize in temperature at the outlet. Heat transfer is maximized if the temperatures are kept as far apart as possible. Here's a generic "coil characterstic curve" from the HVAC industry. This is for a multipass tube/fin heat exchanger with constant airflow. The curve for our radiators will be even steeper. What it shows is that you've almost maximized your heat transfer with only 50% of the water flow. The engine block is also a heat exchanger, probably closer to this curve than the radiator. |