Study On Coupling Rule Between Flow And Heat Transfer Of Foam Fluid Pipe Flow

As a kind of compressible fluid. Foam's density, apparent viscosity and other parameters change with pressure and temperature when flowing in the tube. Conversely, distribution of pressure and temperature is also affected by changes of physical properties, and these phenomenons lead to foam has properties of compressible, variable density, variable rheological index in flow process. This is a coupling non-linear question. Research on this question has importance for completing foam tube current flow properties and enriching non-Newtonian fluid mechanics. Research started from viscous heat generation question of variable parameters power law fluid flowing in the fields which between two planes. On the basis of force equilibrium equation and energy equilibrium equation, equation was scattered through finite difference.Then distribution of velocity and temperature of power law fluid between two planes was solved through chasing algorithm. Calculated results are in accordance with theoretical results, which, indicates the feasibility and convergence of finite difference method solving coupling questions. Coupling with properties of foam fluid, advantages of power law flow pattern was verified through experiments. Using tensor quantity, transforms of continuing equation, motion equation and energy equation between arithmetic coordinate and cylindrical coordinate were realized. On principle of from easy to complex, calculation programs were obtained. Flowing and thermal conduction coupling law of foam fluid in annular, inner tube moving annular and simplified well bore was studied. Under different situations, affecting factors of consistency coefficient, power law index and thermal conductivity were studied respectively one by one. Research proposed changing laws of velocity, temperature, density in wellbore, pressure in wellbore and other parameters at conditions of existing pressure gradient, thermostatic wall or existing heat transfer with formation. Main affecting factors to physical properties were also studied under the condition of multi-variables.Foam clean_up program was formulated., which can anticipate the pressure, foam density and foam quality of form when flowing in the wellbore, Using this program, such parameters as depth of circulation point, nitrogen delivery capacity, base fluid delivery capacity of foam, foam density and equilibrium wellbore injection pressure can be obtained, which can provide foundation for field foam clean up.