Accounting for Density Front Energy Losses

The classical theoretical model of density front propagation is based on a momentum equation for the whole fluid depth and an energy balance for one of the two layers. However, it is not always obvious which layer satisfies the assumption of energy conservation. Wood and Simpson's analysis of internal bores, which assumed energy conservation in the converging ambient fluid layer, is compared with an alternative solution based on energy conservation in the diverging layer. Both solutions are physically realistic because neither predicts an energy gain in the nonconserving layer but the alternative solution gives better agreement with the experimental data.