| such that the only variable in it is the radiator itself. However, keep in mind that this does not mean that the coolant flow rate and the cooling air flowrate are going to be the same. The coolant flow rate and the cooling air flowrate are going to vary dependent on the core design, which are effects due to the core design itself. What we hold the same with respect to these two parameters is the amount of energy we are using to drive the pump and the fan, which is constant given the fact they have their respective impedance and are being supplied a consistent voltage. The fact we are using an electric water pump vs. a mechanically driven pump with fixed pump speed will actually benefit the results of the test. As flow capacity of the cores differs depending on design, even if we were using a fixed speed water pump, the flowrate of the core will have an influence on the test result - this is a given. By using an electric water pump, the pump speed will be affected by the core's flow capacity, but this effect works in the same direction on heat dissipation as core flowrate. What this means is that by using an electric water pump for the testing, the difference in the effect of heat transfer due to coolant flowrate will be exacerbated to some degree and help to spread the results out. It actually is beneficial in this type of dynamic test I am performing - not so for steady state testing. The fact I am using an electric water pump for the testing vs. using an OEM pump does have a consequence. The efficiency of a radiator is notably affected by the coolant flow rate. As the design of the core is changed, it will have a differing sensitivity and response to changes in flowrate which is non-linear. This non-linearity is due to the relationship between flow velocity and the fluid (coolant) boundary layer. Things get real complicated really quickly when trying to take a purely theoretical approach to the analysis. It ends up going to a point where you are making so many assumptions on the variables that you completely lose context with the scope of the result you are looking for. With this in mind, I have already anticipated adding further to the test by strapping an OEM pump to the rig and measuring its flowrate at varying speeds and then further refining our test process.
Enthusiasts soon understand each other. --W. Irving.
Are you an enthusiast? If you are out to describe the truth, leave elegance to the
tailor.
Albert Einstein
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