Experimental Study On Rheology And Sand Carrying Rule Of Multiphase Foam System

In recent years,a new technology for fracturing construction using multiphase foam instead of conventional foam has been developed.The multiphase foam is a foam obtained by adding nanometer or micron particles to the conventional foam fluid.The characteristics,such as viscosity,density and stability,are changed by particles,resulting in the change of rheology and sand carrying capacity of the foam.Therefore,the rheology and and carrying capacity of the multiphase foam system need to be studied.In this paper,the surface rheology,bulk rheology and sand carrying rule of SiO₂/SDS multiphase foam system are studied by experiments.The effect of SiO₂ nanoparticles on interfacial rheology is analyzed.The rheological parameters of SiO₂/SDS foam under different conditions are obtained,and the effects of SiO₂ nanoparticle concentration,foam quality and fluid temperature on bulk rheology are investigated.Moreover,the law of SiO₂/SDS foam sand carrying capacity is researched by analyzing the influence of different factors such as the SiO₂nanoparticle concentration,foam quality and foam flow rate,to provide theoretical basis for on-site multiphase foam fracturing.The experimental results show that interfacial viscoelasticity of the multiphase foam is enhanced by adding SiO₂ nanoparticle,and the slip stress is also increased.Besides,the interfacial viscoelasticity and slip stress are positively correlated with the SiO₂ nanoparticle concentration.The SiO₂/SDS foam system belongs to the power law fluid when the foam quality is in the range of 50%⁸5%,and its rheological properties can be described by power law model.The rheological index of the system decreases with the increase of SiO₂concentration,indicating that its non Newtonian property enhances with the increase of SiO₂concentration.Meanwhile,with the increase of foam quality,the viscosity of SiO₂/SDS foam increase,and the rheological index decrease,but with the increase of fluid temperature,the viscosity of SiO₂/SDS foam decrease,and the rheological index increase.When the concentration of SiO₂ is low,the increase of SiO₂ concentration has little effect on the sand carrying capacity of the SiO₂/SDS foam.When the concentration of SiO₂ is high,the sand carrying capacity increases first and then decreases with the increase of the concentration of SiO₂.In addition,the sand carrying capacity increases with the increase of foam flow rate?velocity?,with the increase of foam quality increases first and then decreases.