| 摘要 |
This invention relates to a method for one dimensional simulation of multiphase fluid flow in pipelines enabling determination of pressure drop, fluid volume fractions, and heat and mass transfer coefficients in multiphase pipeline flows, wherein the method comprises providing real world values of the superficial velocities of each of the continuous fluid phases, the pipe diameter, and the inclination angle of the pipeline relative to the horizontal plane, providing initial values describing the flow geometry of the multiphase flow, where the initial values at least comprises the axial pressure gradient and the positions of the large scale interfaces separating the continuous fluid phases, employing a one-dimensional numerical model based on Eulerian formulated transport equations of the multiphase flow in the pipeline, solving the numerical model with the set of input values from step a) and b) to determine the flow parameters of the multiphase flow, and displaying one or more of the determined flow parameters. |
| 主权项 |
1. A method for determination of flow parameters of a multiphase flow in a pipeline, where the multiphase flow comprises a plurality of stratified continuous fluid phases separated by large scale interfaces, wherein the method comprises:
a) providing estimated or measured input values describing the pipe diameter and the inclination angle of the pipeline relative to the horizontal plane, b) providing estimated or measured input values describing the axial pressure gradient and the flow geometry of the multiphase flow, where the estimated or measured input values of the flow geometry at least comprises the positions of the large scale interfaces separating the continuous fluid phases, c) employing a numerical model based on Eulerian formulated transport equations of the multiphase flow over a vertical cross-section of the pipeline, and d) solving the numerical model with the set of input values from step a) and b) to determine one or more of the flow parameters of the multiphase flow selected from of the list comprising; profiles of phase- and field velocities, profiles of phase- and field volume fractions, profiles of field droplet- and bubble sizes, and phase- and field superficial velocities, wherein the method further comprises: dividing the cross-section area of the pipeline into a number of n discrete horizontally oriented slices by defining a set of n−1 horizontally oriented parallel grid lines spaced a vertical distance apart from each other, where n is an integer from 2 to 1000, defining the position of the nearest lying grid line of each of the large scale interfaces to be the same as the position of the respective large scale interface, defining, for each of the n slices, a set of ensemble averaged two-dimensional Eulerian formulated transport equations for conservation of mass, momentum, turbulence fields, energy, and size of the dispersed field phases for both the continuous phase and each dispersed field in the continuous phase of the n'th slice, averaging the two-dimensional Eulerian formulated transport equations for each of the n slices in horizontal direction over the width of the n'th slice to provide one-dimensional Eulerian formulated transport equations for each of the n slices, and closing the one-dimensional Eulerian formulated transport equations by coupling field values for each of the n slices to pipeline wall boundary conditions and the value of the corresponding field value of the neighbouring slice, determining, for each of the large scale interfaces, the fluxes of mass, momentum and energy across the large scale interface by employing standard wall functions and relating these fluxes to the field values of the slices on both sides of the large scale interface, and employing the dispersed phase volume fractions and concentration of the dispersed phases as boundary conditions on the large scale interface. |
