Study On The Foam Fluid Hydraulic Calculation

At present, the foam fluid has shown enormous potential applications and has a very broad application prospects in the oil industry. This paper, based on the application of foam fluid in petroleum engineering as the background, makes a systematic research aim at the concept of foam fluid, rheological properties, the rheological model and friction coefficient and such as features. These are the basis of calculating foam fluid hydraulic parameter and guiding the theoretical of field operation.Foam fluid is a kind of gas-liquid dispersion system. Its density is low, lightweight, and its pressure is very small. Foam fluid has certain viscosity. It can be continuous to flow, and so it can carry on water, oil, sand and gravel. It is because of these characteristics of foam fluid. It is widely used in oil and gas development projects. But, the foam fluid hydraulic calculation of the basic theoretical research is still relatively small. The theoretical research seriously lags behind the technology development. During the foam fluid process operations, mainly rely on experience to control the process of some key parameters, such as injection pressure, flow velocity, density, viscosity. These all lack of theoretical support.Research on hydraulic calculation method of foam fluid, we can understand the rheology of foam fluid. By choosing appropriate rheological model, we can accurately calculate analysis and prediction for pressure, such as foam fluid flow parameters, which can finally guide and regulate the foam fluid field operation process.Foam as non-newtonian fluid of gas liquid two phase flow, in the process of wellbore flow, due to the compressibility of gas phase, the density of the gas phase changes with the change in pressure, which changes the density of the foam fluid, cause the change of velocity of flow, in turn influence the distribution of the pressure. Therefore, the hydraulic calculation model needs to solve at the same time continuity equation and momentum equation. In addition, due to the change of wellbore temperature will affect the foam density and the viscosity, it will need to introduce energy equation, and finally establish a closed system of equations, the mathematical model of foam fluid hydraulic calculation. The model can be used in the application of foam fluid, wellhead parameter adjustment and design.Finally compiled the corresponding foam fluid hydraulic calculation software design procedure, and a corresponding example is given, and through the analysis of the calculation results, which are the pressure distribution in the tubing and annulus and foam fluid in the tubing and annulus flow parameters (foam fluid density, mass, flow rate and viscosity, etc.). At the same time, when the foam fluid injection wellbore during operations, through the choice of the two different rheological models:Bingham model and Power-Law model, compares the similarities and differences to changes in flow parameter analysis, draws the corresponding conclusions. Thesis conclusions for foam fluid hydraulic calculation, not only can choose rheology model provides a theoretical reference basis for the foam fluid, but also to guide the foam fluid field application is of great significance.