Abstract:
Methods for calculating irreversible energy losses and rates of heat transfer from computational fluid dynamics solutions using volume integrations of energy dissipation functions contrast with the more usual approach of performing first law energy balances over the boundaries of a flow domain. Advantages of the approach are that the estimates involve the whole flow domain, and are hence based on more information than would otherwise be used, and that the energy dissipation function allows for detailed assessment of the mechanisms and regions of energy loss. The research was motivated by a need to clarify energy losses by haemodynamics in the greater vessels of the human body, in particular, the Fontan connection. For this application irreversible energy losses were calculated using the viscous dissipation function. Streamwise integration of the viscous dissipation function is also used to explore the ways in which different flow structures contribute to energy losses.
