ベルヌーイの定理
As the wording of the principle can change its implications, stating the principle correctly is important. What Bernoulli's principle actually says is that within a flow of constant energy, when fluid flows through a region of lower pressure it speeds up and vice versa. Thus, Bernoulli's principle concerns itself with "changes" in speed and "changes" in pressure "within" a flow field. It cannot be used to compare different flow fields.