Hydraulics of exchange flows

Basic internal hydraulic theory has been extended to include frictional and nonhydrostatic effects for the case of flow over a sill in a channel conne cting two reservoirs of slightly different density. The predictions of the extended theory compare well with laboratory experiments. The inclusion of frictional and nonhydrostatic effects was found to be necessary to accurate ly predict the flow rate, the along-channel variations in interfacial posit ion, the composite and stability Froude numbers, and the internal energy. T he accuracy of predictions of the extended theory is limited by uncertainty in estimates of the interfacial friction factor.