Abstract:

Low permeability unsaturated oil reservoir is studied in this paper.By using Darcy formula，the IPR equation of unsaturated reservoir considering threshold pressure gradient and media deformation is derived.The IPR curve is tested with field data，and threshold pressure gradient，media deformation and water cut are studied respectively to explain how the production is affected.The results show that，the oil production of unsaturated reservoir decreases with increasing threshold pressure gradient and media deformation under the same conditions.The IPR curve contains the maximum oil production when the bottom hole flowing pressure is below the bubble point pressure.Under the same conditions，the maximum production pressure increases with decreasing threshold pressure gradient and deformation factor.Water cut has little effect on oil production.The research can theoretically guide the reasonable development of unsaturated reservoir.

Key words: unsaturated reservoir, media deformation, threshold pressure gradient, IPR curve, low permeability