The formula for the energy \(\boldsymbol{E}\) stored in a region \(R\) is (cf. (1.6.1)):
\[ \boldsymbol{E}=\varrho \iiint\left[\frac{1}{2}\left(\Phi_x^2+\Phi_y^2+\Phi_z^2\right)+g y\right] d x d y d z \]
disturbance rate: \(R U=F\), where \(R\) represents the horizontal resistance and \(F\) the net energy flux into the water.
if \(F=0\)
Greater accuracy still is obtainable by expanding $\{t+(n+r+1) \ln t\}$ to higher powers of $(t-x) / x$.