Hydrodynamic model of two-phase pipe flow

A main objective of the advanced computer code development effort is to attain economy in computing time while retaining accuracy of results. With this objective in mind, a lumped parameter model has been developed for describing transient two phase flow in a pipe on the basis of the four conservation equations of the drift flux model. In order to assess computing speed and accuracy of the lumped parameter approach, a discrete parameter method has also been developed based on the same basic model. In the lumped parameter approach, the governing partial differential equations have been reduced to ordinary differential equations in the time coordinate by use of shape functions or profiles which describe the spatial distribution of the variables within the component. In the discrete parameter method, a first order implicit Euler formulation for the governing equations has been used to develop a computer algorithm capable of solving problems with implicit boundary conditions.