Abstract: Method intended for real-time modelling, by neural networks, of hydrodynamic characteristics of multiphase flows in transient phase in pipes. In order to specifically take account of the possible flow regimes of fluids in pipes, various neural or “expert” models are formed for several flow regimes (or subregimes) in the whole of the variation range of the hydrodynamic characteristics of the flows (preferably for each one of them), as well as a neural model estimating the probability of belonging of the flows to each flow regime or subregime, knowing some of the characteristics thereof. The probabilities obtained are used for weighting the estimations delivered by each neural model, the result of the weighted sum being then the estimation eventually retained. Applications to various industries and notably for modelling of hydrocarbon flows in pipelines.

Abstract: Method intended for real-time modelling, by neural networks, of hydrodynamic characteristics of multiphase flows in transient phase in pipes. In order to specifically take account of the possible flow regimes of fluids in pipes, various neural or “expert” models are formed for several flow regimes (or subregimes) in the whole of the variation range of the hydrodynamic characteristics of the flows (preferably for each one of them), as well as a neural model estimating the probability of belonging of the flows to each flow regime or subregime, knowing some of the characteristics thereof. The probabilities obtained are used for weighting the estimations delivered by each neural model, the result of the weighted sum being then the estimation eventually retained. Applications to various industries and notably for modelling of hydrocarbon flows in pipelines.

Abstract: Method intended for continuous detection and control of hydrate formation at any point of a pipe carrying multiphase petroleum fluids. The method uses a compositional code allowing to simulate the circulation modes and conditions at any point of the pipe, considering that the fluid mixture is substantially continuously at equilibrium, that the composition of the multiphase mixture is variable all along the pipe and that the mass of each constituent of the mixture is globally defined by a mass conservation equation regardless of its phase state. The thermodynamic hydrate formation conditions are detected after a particular stage of grouping the petroleum fluids into pseudo-components so as to isolate the hydrate forming components, with definition for each one of a mass fraction and of a certain number of characteristic physical quantities, and the data relative to these particular fractions are applied to the modules so as to determine at any point the hydrate dissociation temperature (Td).

Abstract: A method for forming a module (hydrodynamic or thermodynamic for example) intended for real-time simulation of the flow mode, at any point of a pipe, of a multiphase fluid stream comprising at least a liquid phase and at least a gas phase. The method comprises using a modelling system based on non-linear neural networks each having inputs for structure parameters and physical quantities, outputs where quantities necessary for estimation of the flow mode are available, and at least one intermediate layer. The neural networks are determined iteratively to adjust to the values of a learning base with predetermined tables connecting various values obtained for the output data to the corresponding values of the input data. A learning base suited to the imposed operating conditions is used and optimized neural networks best adjusted to the imposed operating conditions are generated.

Abstract: Method intended for continuous detection and control of hydrate formation at any point of a pipe carrying multiphase petroleum fluids. The method uses a compositional code allowing to simulate the circulation modes and conditions at any point of the pipe, considering that the fluid mixture is substantially continuously at equilibrium, that the composition of the multiphase mixture is variable all along the pipe and that the mass of each constituent of the mixture is globally defined by a mass conservation equation regardless of its phase state. The thermodynamic hydrate formation conditions are detected after a particular stage of grouping the petroleum fluids into pseudo-components so as to isolate the hydrate forming components, with definition for each one of a mass fraction and of a certain number of characteristic physical quantities, and the data relative to these particular fractions are applied to the modules so as to determine at any point the hydrate dissociation temperature (Td).

Abstract: Method for forming a module (hydrodynamic or thermodynamic for example) intended for real-time simulation of the flow mode, at any point of a pipe, of a multiphase fluid stream comprising at least a liquid phase and at least a gas phase, so that it is best suited to fixed operating conditions concerning a certain number of determined structure and physical parameters relative to the pipe, and a set of determined physical quantities (hydrodynamic or thermodynamic quantities for example), with fixed variation ranges for the parameters and the physical quantities.

Abstract: The invention provides a model representative of steady and transient flows, in a pipe, of a mixture of multiphase fluids, which takes account a set of variables defining the properties of the fluids and of the flow modes having separate phases which are dispersed and intermittent, and the dimensions and slope of the pipes. The modeled quantities characterizing the flow are determined by solving a set of transport equations, an equation of mass conservation per constituent and an equation of momentum of the mixture, and by using a hydrodynamic model and a hydrodynamic model of the fluids. The models are formed by considering the mixture to be substantially at equilibrium at all times and that the constituents of the multiphase mixture are variable all along the pipe. The method can be applied to hydrocarbon transportation network study and to determination of characteristics of flow of the multiphase mixture in the pipe.