Study On Prediction Of Horizontal Well Production Capacity In Bottom Water Reservoir

How to accurately predict the steady-state productivity of a horizontal well in bottom water drive reservoirs is particularly important during the period of reservoir production, as more horizontal wells are being used in bottom water drive reservoirs.This article mainly studies the bottom water drive reservoir in Xinjiang Luliang oil field, through comprehensively applying analytical method and numerical simulation method to analyze the horizontal well production capacity, critical rate and reasonable liquid producing capacity, main research achievement are as follows:(1) Through investigating and studying these articles about horizontal well productivity at home and abroad, we analyze the conventional horizontal well productivity prediction model and the model, which are widely used in bottom water drive reservoirs. We take horizontal wells of bottom water drive reservoir in Xinjiang Luliang oil field as an example, from horizontal segment effective length, reservoir effective thickness, horizontal permeability, vertical permeability, radius of oil drainage area, horizontal section vertical position analyze and evaluate influencing factors of horizontal well productivity.(2) Through building typical model of a single horizontal well, we comprehensively apply the numerical simulation method and analytical method to analyze the flexibility of horizontal well productivity formulae in conventional reservoirs and bottom water drive reservoirs, and select the reasonable formula of productivity in different horizontal permeability, the ratio of vertical permeability and horizontal permeability, reservoir effective thickness, and so on.(3) In this paper, we analyze the water cresting in bottom water drive reservoirs, calculate the critical rate of typical horizontal wells in Xinjiang Luliang oil field bottom water drive reservoir. The result shows that the critical rate, which calculated by Guo&Lee formulae is close to the average productivity before the breakthrough of bottom water in actual production. Therefore, we recommend the equation of Guo&Lee to calculate the critical rate in bottom water drive reservoir of Xinjiang Luliang oil field.(4) According to the actual production of Xinjiang Luliang oil field, we define the reasonable liquid producing capacity, which is suitable for horizontal well in this oil field, and we use the numerical simulation method to build typical model and draw the curve about oil production and liquid production, which can analyze the reasonable liquid producing capacity. Meanwhile, we analyze the effect of horizontal permeability, the ratio of vertical permeability and horizontal permeability, reservoir effective thickness, horizontal section vertical position.Through this study, the horizontal well productivity prediction model in bottom water drive reservoirs, critical rate formulae and the determining of reasonable liquid production are not only important guiding significance to the study block, but also has important reference value for the development of similar reservoirs in China.