主题：关于FEMM 4.0

以下是引用Acoustics在2006-10-06 18:12:42的发言：
 
The inductance of an air core solenoid coil can be calculated with Wheeler's formula:

L (microhenries) =	0.8 * N^2 * R^2                 6*R + 9*L + 10*B
N = total number of turns R = average radius = (inner radius + outer radius)/2 L = coil length (along the axis) B = thickness of the winding = outer radius - inner radius Refer to Figure 1 below. (all dimensions in inches)
Alternatively, for dimensions in millimeters:
L (microhenries) =	0.0315 * N^2 * R^2                6*R + 9*L + 10*B

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Figure 1