A Review of Inflow Performance Relationship of Conventional Reservoirs and Unconventional Reservoirs

Inflow performance relationship (IPR) as a critical method representing the deliverability of well has been used for a long period in the petroleum industry. This method is proposed in the form of simple correlations of flowing bottom hole pressures (BHP) and flowing rates of wells from the very beginning and has been continuously developed in the following time. In recent years, the appearance of new types of IPRs extends the original concept of IPR and expand its application areas. This work reviews different IPR methods that are proposed from a very early time to recent times. There are three main types of IPRs introduced in this paper that are classified as follows: the traditional (steady or pseudo-steady) IPRs for conventional reservoirs, the transient IPRs for unconventional reservoirs experiencing long-term transient flows, and the dynamic IPRs for coupled reservoir-wellbore systems. The calculation principles, applicable conditions, advantages and disadvantages of the above three types of IPR are discussed. In addition, the advanced artificial intelligence techniques, as a hot trend in all engineering areas, that utilized to generate IPRs are summarized, such as the artificial neural network and fuzzy mathematics, etc. Finally, the future research work is prospected. The review of the development of IPRs can provide a better view of the current research levels of productivity research and identify existing research issues and directions for future development. At the end of the paper, some open suggestions for future work are mentioned.