Pre-processing of stop pump pressure test data
Bottom-hole pressure conversion for variable density and flow
During fracturing, different types of fracturing fluid are injected and sand adding is also required. The viscosity, density and so on physical parameters of different types of fluid will produce complex flow in the wellbore，so that the calculation method of converting the wellhead pressure to the bottom hole pressure is very complicated. According to the principles of mechanical mass conservation, momentum conservation and energy conservation in wellbore, this project establishes the vertical pipe flow equation of wellbore considering variable density and fluid physical property, and adopts Longer-Kut method to solve the equation, so as to ensure the accuracy of the wellhead pressure converted to the bottom hole pressure, and to provide guarantee for the correct interpretation and analysis of the stop pump pressure.
Filtering elimination of water hammer pressure after stop pump
The pressure oscillation produced by stopping pump, that is, water hammer effect, has a great influence on the pressure and derivative curve in the early stage. In order to better analyze and explain the stop pump pressure data, it is necessary to process the pressure data after stop pump fracture by filtering.
Analysis of stop pump pressure data software
The bottom-hole pressure solution of multiple stage fracture horizontal well in Laplace space and physical space
Multi-stage fracturing horizontal well stop pump data analysis plate drawing
According to the number of different fractures, different fracture length and different permeability, different pressure and derivative double logarithmic plate are obtained. Because of the many parameters in horizontal well fracturing, we propose to manage the graph plate according to the importance of curve parameters, size order and so on, which is beneficial to improve the speed of curve simulation.
Stop pump data analysis for each layer of pressure data
Through the analysis, we can obtain: the half length of each fracture, the diversion capacity, and the parameters such as permeability, area and average pressure in the SRV area.
Interpretation and evaluation of report preparation
Based on the test and analysis, combine the drainage reality, the influence of different drainage methods on the seepage capacity of gas-water reservoir two-phase flow is studied. At the same time, the stress state is evaluated by using the pressure recovery well test results.