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The boundary layer height that should be captured is represented by δ99 on the calculator. By leaving viscosity and density as their default values, the length scale as ½ the circumference of the battery cell (as any given air particle in the boundary layer passes over ½ of the battery at one time), velocity as the free-stream velocity (which should ideally be a good starting point is equal to the inlet area divided by the area displaced by the battery cells at their widest point, all multiplied by the inlet velocity, however, a preliminary simulation with coarse settings will find a better free-stream velocity), and any number of layers. I have accidentally used the inlet velocity before, but the simulations have still converged.
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