Dynamic Simulation Of Thermal Coupling And Production Optimization Of Steam Stimulated Horizontal Wells In Chunguang Oil Field

At present,the steam stimulation horizontal well in Chunguang Oilfield have the problems of huge heat loss along the wellbore,poor effect of steam injection,complex stress on pipe,sucker rod breaking when operate frequently,the pipe bending after steam injection in the development process,it has seriously effected the normal oil production.To solve the above problems,the paper has carried on the thermal coupling dynamic simulation on the wellbore and formation fluid(steam)steam injection in the steam stimulation horizontal well,it has established the wellbore fluid(steam)temperature and heat loss calculating model and wellbore fluid(steam)temperature and heat loss calculation model in different wellbore viscosity reducing technology,it has used reservoir numerical simulation software,calculated and simulated the rules of fluid temperature field and viscosity field in injection-production process.It has carried on the thermal coupling dynamic simulation on the sucker rod and tube in the production of steam stimulation horizontal well and injection-production tubing string and production optimization in middle deep and super heavy oil in Chunguang oilfield.And on this basis,it has developed corresponding software,it provided a management means and methods for the Chunguang oilfield production.It used the software to simulate the calculation process by the date of the steam temperature,the pressure and the dryness in wells of L31713 and G51117 and the date of oil temperature and the maximum and minimum suspension point load of 10 other wells,the calculation results and field test results were compared and analyzed,the average relative errors were 2.56%,1.425,3.67%,7.32%,7.49%.The calculation results show that the calculation model has high precision and meets the requirement of engineering application.Different well completion methods have no effect on the temperature,pressure,dryness and heat loss of the wellbore fluid in the process of steam injection;The effect of throttling on the steam pressure,temperature,dry degree and heat loss in wellbore is small,which is 4.59%,1.1%,2.19% and 0.75%;.The calculation results show that the mixing light oil had a better effect of viscosity reduction than electric heating.It shows that the fatigue failure of the sucker rod is the main reason of sucker rod broken off by the force and motion state analyses of sucker rod,it suggests that the long stroke and small punch production canreducing the sucker rod break off.The effective suction length of uniform steam injection is longer than that of general steam injection,and the method of multi point steam injection is recommended in the field of 98 m.The heat pipe dryness in downhole can be increased by more than 20 percentage to the process of steam injection than ordinary tubing;The bushing can make wellbore steam increased 4.5 percentage;the ring empty nitrogen injection annulus can improve steam is about 4.8 percentage points than no nitrogen injection,it suggests to use the process measures of "Insulated tubing + Bush + annulus injection of nitrogen.It had the parameter optimization of injection and production,the result shows that the optimal injection production parameters for dry cycle steam injection quantity is 1600 t,the speed of steam injection is 200t/d,the steam injection is bigger than 0.7,the soak time is 3d,bottom hole flow pressure is 2MPa.It had made sure the time of decrease viscosity and turn the wheel by calculating the lowest oil temperature and oil production in safe suspension point load and torque.The paper provide an important guidance for the production and management of the Chunguang oilfield.