Font Size: a A A

The Elastic Viscosity Theory And Application Of Polymer Solution

Posted on:2005-04-15Degree:DoctorType:Dissertation
Country:ChinaCandidate:X S ZhengFull Text:PDF
GTID:1101360125452396Subject:Oil and gas field development project
Abstract/Summary:PDF Full Text Request
When polymer solution flow in porous medium, the properties of polymer solution will cause drastic elastic flow if flow rate is up to critical viscoelastic flow velocity. According to the investigation actuality of viscoelastic behavior for polymer solution, theory and experiment on rheological characteristic, elastic viscosity, elastic viscosity in the porous medium of polymer solution and the elastic viscosity apply of polymer solution on polymer flooding are studied systematically. The research results of the paper are as follows:The rheology and the rheology influence factors of HPAM solution are studied through the measure of polymer solution's rheological behaviors. Based on steady shear experiment, it shows that the shear viscosity of polymer solution increase with the increase of molecular mass, concentration, with the decrease of shear rate. Based on the dynamic mechanical tests, it shows that the viscoelastic behaviors of polymer solution increase with the increase of molecular mass and concentration.According to Rouse-Bueche-Zimm (RBZ) theory, based on the relaxation formula of dilute polymer solution derived by Bird with finite-extensible, non-linear elastic (FENE) dumbbells molecular model, the relaxation formula of FENE dumbbells model of dilute polymer solution is extent to thick polymer solution, and the relaxation formula of thick polymer solution is established, the formula not only is applicable to the dilute polymer solution, but also be applicable to the thick polymer solution. Based on steady shear experiment, it shows that the variety regulation of relaxation time along with shear rate computed by new derived formula is same alike with the variety regulation computed by RBZ theory.Based on the molecular theory of polymer rheological in simple steady elongation flow, the macromolecules are treated as finite extensible, nonlinear elastic dumbbells. At the low elongation rate and high elongation rate, the elastic viscosity formulas of dilute polymer solution are deduced. Hydrodynamic interactions are accounted for approximately by using the equilibrium-averaged Oseen tensor, and the formulas for elastic viscosity with hydrodynamic interactions are established for flow of dilute polymer solution applicable at low and high elongation rates. The elastic viscosity formula of dilute polymer solution with hydrodynamic interaction is extent to thick polymer solution, the elastic viscosity formula of thick polymer solution with hydrodynamic interaction is established. The elastic viscosity with hydrodynamic interaction is compared with the elastic viscosity without hydrodynamic interaction. Consequently, the hydrodynamic interaction included in a microscopic model of molecules gives rise the significant effect on the macroscopic properties of dilute polymer solutions, the additional stretching of dumbbells is yielded by the hydrodynamic interaction, the elastic viscosity is increase, the elastic effect is boost up. The critical Deborah number of polymer solution with hydrodynamic interaction is lower than that of polymer solution without hydrodynamic interaction.Based on the seepage experiment of HPAM solution flow through artificial core, when flow rate is higher than critical viscoelastic flow rate, the pressure curve of polymer solution flow in porous medium would show the viscoleastic effect. Based on the Deborah number formula of dilute polymer solution flow in porous medium and the effective elastic viscosity formula used by composite resistance factors established by Durst with FENE dumbbells molecular theory, the formulas of Deborah number and effective elastic viscosity of thick polymer solution are established, the formula not only is applicable to the dilute polymer solution, but also be applicable to the thick polymer solution. The seepage experiment of HPAM solution___________________________flow in porous medium show that the variety regulation of effect elastic viscosity along with Deborah number in porous medium is same as the variety regulation of elastic viscosity along w...
Keywords/Search Tags:polymer solution, elastic viscosity, viscoelastic behavior, dumbbell molecular model, Deborah number, porous medium, displacement efficiency
PDF Full Text Request
Related items