Integration of river water temperature constraints within real time operation of hydroplants

摘要

The problem of water temperature constraints is studied for the operation of cascading hydroplants in steady and unsteady flow regimes. Simplified hydrodynamic and transport equations, as well as numerical simulations over rectangular channels and complex river systems, are used to give useful trends with respect to the controlling parameters. Implementation into a short term optimization model is discussed. For the steady case, it is shown that the temperatue increase due to the presence of a heat souce can be well approximated as a function of flow only, and that the imposition of a minimum flow requirement, constant voer the scheduling horizon, is sufficient to provide proper control. For the unsteady case, the temperature increase is a function of downstream water depths and the boundary condition. A simple rule involving the summation of the upstream flow over time is suggested to allow for variable loads.