Key Technical Features of DynaLift™ Software
Completion
Detailed completion modeling allows the user to enter data for variable tubing strings and annular casing strings. Comprehensive pressure drop calculations are then performed for the injection gas and the produced fluids. Accurate temperature calculations are applied to produced fluids as they rise through the completion.
Gas lift unloading sequence, showing amount of gas flowing through each of the valves as a function of time.
|
Gas Lift Valves
Typical generic valve performance curves are provided and various manufacturers performance curves are available from the Valve Performance Clearing House. These can be selected on a case-by-case basis for each of the mandrels installed in the completion. The simulation can be stopped, and valves changed or a simulation of valve failure made, to evaluate the impact on the system performance. Accurate modeling of gas lift valve performance is the heart of an accurate modeling of the system and DynaLift software performs a detailed calculation of the force balance, stem travel, and resulting gas passage and pressure drop for each valve at each step of the simulation.
Simulation of valve erosion due to unloading of well fluids.
|
Reservoir
Reservoir inflow and injectivity is an integral part of modeling well performance. A correctly designed gas lift completion will take account of the reservoir performance. DynaLift software correctly models the initial drilling fluid production during the early stages of the gas lift unloading. At later stages in the gas lift simulation the well flowing pressure will be determined in part by the productivity of the reservoir. It is important to realize in the design process that when the well is lifting off bottom the amount of produced fluids will be determined as much by the inflow performance as by the gas lift design.
Study of well stability as function of gas injection rate.
|
Controls
The simulation is started from a definable set of starting conditions and allows the user to control the unloading method. Choke settings are provided for both injection and production chokes and the unloading method is selectable. The appropriate controls are adjustable while the simulation is running to allow different scenarios without having to start again.
Output
The software outputs data in graphical form for the dynamic flowing gradient, wellhead pressure, wellhead flow rate, valve performance (gas and liquid passage), and reservoir flow with bottom hole pressure. Output data can also be captured in a file for later analysis as the simulation progresses.
|
