Research On Calculation Method Of Thermodynamic Parameters Of Steamsoaking Horizontal Wells

Steamsoaking horizontal wells have been widely paid attention to in recovery heavy oil fields because of their particular advantages and characteristics. Research on calculation method of thermodynamic parameters of steamsoaking horizontal wells in injection-production process and simulation on changes of wellbore/formation temperature and pressure with time can find out variation regularities of the different parameters. They provide scientifid basis of better application of this technology.The paper used the discretizing wellbore model, established the model of cyclic steam soaking of single horizontal well. Firstly, in accordance with variable mass flow of horizontal wells and law of conservation of mass, law of conservation of momentum and law of conservation of energy principle,we set up models of the steam pressure, dryness, temperature and amount of steam absorption distribution along the horizontal segment in steam injection period.Secondly, based on systematic study on fluid mechanics and heat transferring characteristics of horizontal wells recovering heavy oil in injiection-production process, considering the heat conduction and convection in the reservoir, as well as heat loss of the upper and lower rock covers,etc. By means of the mass conservation principle and energy conservation principle, horizontal wells steam soaking heating radius model and formation temperature/pressure distribution model before and after shutting in well have been built. Taking into account of horizontal wellbores characteristics of variable mass flow and seepage coupling with formation, we established wellbore pressure, temperature and production prediction models in production period. Method to solve model was numerical method. Then we composed program and applied caoqiao 27 5 horizontal well datas and verified the calculation procedure.