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Hey, folks. I'm using a Nissan Leaf motor and inverter in my current build. I am also using a Lear charger. All of these are liquid cooled, and I intend to put them all in the same loop. Do you see any problems with that beyond possibly the size of the ports on the components? I see that the heat exchanger in a Leaf is pretty sizable, as well, so I want to be sure that the one I select is large enough. The core in the Leaf is about 28"x12.5".

Increasing the capacity of the cooling system would also allow me to run the motor and inverter a little harder, yeah?
 

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Heat flux (unit is Watt) is proportional to the temperature difference (kelvin, but essentially celsius), surface area and resistance (unit w/m^2.K).

Assuming stock cooling paths in your leaf components, your resistance and surface area are fixed, so your options to allow the components to produce more heat without increasing temperature are to reduce the coolant temperature (larger radiator and/or better airflow) and increased coolant flow. In both cases you'd need a more powerful pump.

By putting your components in series, you're reducing the amount of heat the second and third components can transfer into the coolant, because the increased input temperature reduces the temperature difference, hence reduces the heat flux.

The ideal system would be parallel loops with electronically controlled valves to limit flow to the component(s) needing less cooling, so more flow reaches the hotter component, or one pump per loop.
 

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While putting them in series does reduce effectiveness, it's not as extreme as it first appears.

The motor and inverter should never need cooling at the same time as the charger. The main thing I'd be concerned about is making sure you have enough air flow over the radiator when the car is stopped and charging.

Is this a level 2 charger or a DC fast charger?
 

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Discussion Starter #4
It's a 3.3Kw Lear charger, so I suppose its level 2. I intend to use the stock Leaf radiator and fans for the circuit, which should be way overkill for charging.

Sent from my SM-N960U using Tapatalk
 
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