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1 junction

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1 junction

Suppose we have the following 1 junction with one bond (1) pointing towards the junction and two bonds (2 and 3) pointing from the junction.

 1 For a 1 junction the flows are always equal! This means:

f1 = f2 = f3

 2 The junction is power continuous. For the figure above this means:

e1×f1 = e2×f2 + e2×f2

 3 Combining 1 and 2 yields:

e1 - e2 - e3 = 0

The last equation can also be derived with the rule of thumb: All effort of the bonds pointing towards a 1 junction should be added and all efforts of the bonds pointing from the 1 junction should be subtracted.

The first equation, limits the causality. Only one bond may have an flow-in causality (the stroke pointed from the 1 junction). All other bonds must have (seen from the 1 junction) a flow-out causality (strokes pointed towards the 1 junction). For the example junction this means three possible causal forms can exist: