Analyzing the data of the previous tests on the track, we quickly realized that it would be the case to make a test bench study, in the true sense of the term. We began to think about how to build a test system of these components related to the typical cooling systems of karts, starting from the heart: the water pump. Like many things, easy to say, a little less to do… Starting from the evaluation of the type of forces in the field: how much power does the pump absorb? And what type of flow should we measure? Here a little help came to us from the manufacturer who declared a maximum flow rate of about 30 liters / min.
For the construction of the test bench we used a brushless electric DC motor with a maximum power of 80 watts (0.1 hp). The engine had to be fitted with a specially constructed pulley, and a support for the engine itself. Unfortunately, we did not expect the system to require so much power to operate. We expected the need would not exceed 50/60 W at 8000 rpm. Instead, it required 70 already at 3000 rpm … Too optimistic! So the demand for such energy did not currently permit us to exceed 3500 rpm of the motor-pump system. However, if nothing else, we reached the maximum capacity already at this speed. This will oblige us to look for power to supply the electric motor and thus be able to study in the next episodes what will happen beyond the threshold of 4000.
The hydraulic part merits a separate discussion. To begin with, the flowmeter found on the market has standard industrial attachments and this allowed us, through a specialized company that was very helpful, in addition to my father Domenico whom I thank, to adapt a series of fittings or junctions of the exact diameter, so as to disturb as little as possible the measurement that had to be made (avoiding, thus, unwished for bottlenecks) and also to create an “instrumented” area that will host other sensors, useful for when we “provide heat”.