Numerical Simulation of Downhole Throttle Atomization Drainage

Abstract

For gas reservoirs with low pressure, low permeability, low yield and widely distributed underground water, the gas wellbore tends to accumulate fluid during production, which seriously affects the production of gas wells. To implement drainage technology, such as coiled tubing and gas lift after water production of gas wells, it is necessary to remove throttles from wells. Therefore, by optimizing the existing throttling technology and the structure of the throttling nozzle, gas wells can drainage gas recovery by relying on the energy of the gas reservoir. In this paper, through optimizing the inner flow channel of the downhole throttle, the liquid flow through the gas nozzle can reach supersonic velocity, realizing ultrasonic attenuation, reducing the critical liquid carrying capacity of gas wells and improving the liquid carrying capacity of gas wells. The liquid atomization effect of gas-liquid two-phase flow through throttle nozzle was simulated using numerical simulation software ANSYS, and the droplet size distribution after atomization under given operating conditions was quantitatively analyzed. The simulation results show that the throttling atomization of sonic nozzles, the particle diameter of the droplets below 70 account for more than 80%, which greatly improves the drainage effect of gas wells and gas reservoir recovery, and extends the life of the gas well.