EK CoolStream CE 140 Radiator Review

The Thermal Data

A total of 6 tests were conducted at 1.0 GPM with fan speeds of 750 rpm, 1300 rpm and 1850 rpm being run in ‘Push Only’ and ‘Push/Pull’. All inclusive this testing takes between 40 – 50 hours of logging time (plus processing the data) to get the results that are presented.

Below is the final data results gathered from at least 5 data logging runs at the flow rate and fan rpm combination. The most stable 15 minute period from each logging run was used and then averaged with the other runs to obtain the data for the table below. A total of 16 temperature sensors are used in the thermal test chamber (8 air in, 2 air out, 3 water in, 3 water out). Each sensor takes a reading every second and is logged via a CrystalFontz unit.

The data in the table below is the averaged results of the logging runs which has then been used to create all the plots and tables there-after.

The performance metric of critical importance is the delta between the warm coolant temperature in and the cool ambient air temperature going into the radiator. Given that the system is well insulated and in equilibrium and we know the heat input to the system then we can also calculate a very important number. That number is the amount of power required to raise the coolant temperature by set amount. That amount is typically 1C or 10C. The latter is a more useful reference point.

Let’s take a look at the Delta T results from the tests. Note that the extrapolation of the curve is much more sensitive to error than in the tested range.

I was not too concerned about the actual delta numbers but instead the trend pattern. As we should expect, the deltas come down significantly as the fan speed is increased.

Delta T results (as above) are not always helpful when thinking about how many radiators you would need to cool your system. Instead it’s more useful to know the metric of W/delta C. This metric is plotted below. It tells us how many watts are dissipated by the radiator when the coolant rises 10C above ambient temperatures. (W/10 Delta T):

This bar chart can be deceiving for comparing performance between the 2 fan assemblies. The average difference at the same fan speed was ~83.5%, but ranged from ~79% at 750 rpm to 88% at 1850 rpm. Without delving deeper into the results these percentage numbers could also leave one with the wrong interpretation of this data so we’ll jump the gun a little to explain this better before moving on.
Starting with the 21% variance at 750 rpm, we conclude that the Push/Pull was much more efficient at heat dissipation than Push Only at this fan speed and resulted in the greater variance between the results.
Likewise but in reverse, the low 12% variance at 1850 rpm can be attributed to Push Only being very efficient while in Push/Pull the efficiency in heat dissipation has dropped off.

This same data can now be plotted on a chart so that an end user can interpolate their own fan speed. Note again that the extrapolation of the curve is much more sensitive to error than in between the tested range.

Using the explanation above, we can see the CE 140’s Push/Pull result does have a great start but is begins to curve over while the Push Only on the other hand has almost a straight line showing more efficient use of air flow as the fan speeds increase.

This correlates well with the Air Efficiency data in our results table. at the top of this page.

Now let’s analyze that data some more…