The Study Of Flow Filed And Stress Inside The Hydrajet Perforating And Fracturing Tool

Hydrajet perforating and fracturing is a widely used technology in stimulating the thin and low permeability reservoir.This technology performs perforating and fracturing job with one string run which significantly save the operation time as well as lower the risk of sticking and plugging the string by sand.However,there is a bottleneck for this technology,which is its relative short life.During the perforating and fracturing process,a large amount of abrasive particles is added into the tool.These abrasives are accelerated by the very high operation pressure thus having very high kinetic energy which make them extremely destructive.When the high-energy abrasives pass through the nozzles they can easily abrase the tool.In order to study the eroded mechanism and improve the life of hydrajet perforating and fracturing tool,it's critical to investigate flow filed and stress inside the tool under working condition.In this thesis,a three-dimensional model for the hydraulic perforating and fracturing tool is established by the graphics software CREO.Then the real downhole working environment for this tool is simulated by ANSYS Fluent.The scenarios of different inlet pressures,different abrasive volume fractions,different abrasive densities and different distances between tool and tubing are simulated.The flow filed,pressure field at the downhole and stress acted on the tool are investigated closely.It is concluded that the upper and lower parts of the nozzles are the largest-stress acting area.By doing all of this,the flow filed and stress inside the tool during under working conditions are studied.At the end,recommendations for improving the tool's life is also given.