Development Of Simulative And Experimental Facility For Heavy Oil Wellbore Based On Distributed Optic Fiber

The temperature and pressure in heavy oil wellbore are important parameters to evaluate the effects of thermal recovery by means of injecting steam. The measurement of the above two parameters has been a difficult problem for a long time, traditional electronical sensors can't keep a long and stable work condition in intricate and severe environment. The measurement based on Brillouin Scattering optic fiber sensor which is developed in recent years will be a widely applied technology in the future, so the paper designs a set of experimental ground device-a simulation wellbore for heavy oil wells, to meet the experimental environment requirements of logging with optic fiber sensor based on Brillouin Scattering.Based on analyzing the technics characteristic of heavy oil thermal extraction by injecting steam, the paper studies features of wellore environment, sets up the wellbore model of temperature and pressure according to thermal transfer and steam water two-phase flowing conditions, then solves the model by using numerical iteration, at last validates it by dint of a computing example.According to the requirements of experimental environment, the paper designs a set of experimental device-a simulation wellbore for heavy oil wells, which contains three parts: a simulation wellbore, a control system of pressure, a temperature thermostat bath. The high pressure container adopts three layers structure, using a supercharger and an external circle temperature thermostat bath to achieve the desired high pressure and temperature, the pressure and temperature in it can be adjusted continuously and controlled, to simulate the wellbore environment.In allusion to the time inertia and delay of temperature control system, the paper studies control arithmetic to be useable. Finish setting up the model of temperature control system, the PID control system, fuzzy control system and fuzzy PID with parameters self tuning are simulated by using Simulink and fuzzy logic tools in MATLAB, then fuzzy PID with parameters self tuning is selected as an optimal control method.The paper designs an automatic pressure control system in theory. The act device adopts electrical-hydraulic control system, builds models for each separated parts, and gets the mathematical models of pressure control system. After analyzing experimental data, take the change of temperature as a disturbance for the pressure in the model, finally the pressure control system is proved stably by simulation.Finally the paper implements on serial communication with MSComm in VB6.0, by means of standard interface supplied by intelligent instruments, develops an data acquire system for an experimental wellbore facility, communicates at a high speed and stably between the device and computers, realizes a series of function, such as data collection, management and so on.