The development of an interpolation technique for reducing the computational run time associated with the numerical simulation of highly turbulent two-phase flow such as that following the rupture of pressurized pipelines is described. The model is validated by comparison against the results of the pipeline rupture tests conducted by BP and Shell Oil on the Isle of Grain as well as intact end pressure data relating to the MCP-01 riser rupture recorded during the Piper Alpha tragedy. Apart from producing good agreement with the measured data, significant (ca. five-fold) reduction in the computation run time is obtained as a result of the introduction of the interpolation technique.