Discussion of the New Models for Composite Reservoir Pressure Transient Analysis

  IJETT-book-cover  International Journal of Engineering Trends and Technology (IJETT)          
  
© 2016 by IJETT Journal
Volume-38 Number-4
Year of Publication : 2016
Authors : Ashkan Jahanbani G., Tom A. Jelmert
DOI :  10.14445/22315381/IJETT-V38P238

Citation 

Ashkan Jahanbani G., Tom A. Jelmert"Discussion of the New Models for Composite Reservoir Pressure Transient Analysis", International Journal of Engineering Trends and Technology (IJETT), V38(4),214-217 August 2016. ISSN:2231-5381. www.ijettjournal.org. published by seventh sense research group

Abstract
Enhanced oil recovery (EOR) projects such as steam injection into an oil reservoir are usually analysed using composite reservoir models consisting of two regions separated by a vertical front. This simplification may lead to errors in the estimates. To overcome this, analytical models have been recently proposed taking into account some of the effects such as gravity, heat loss and gradual change of properties that are overlooked in the conventional models. In this paper, description and comparison of the recent models is given showing the differences due to different ways of treating gravity effect and variation of properties in the intermediate region(s). For a better representation of the composite reservoirs, it is suggested to apply these new models with tilted fronts and smooth change of the properties in type curve matching for improved well test analysis. Multi-region multi-layer composite model is an extension of the conventional models that can be improved by adding more intermediate regions and thin skin at the front locations. This model can reasonably match the recently developed models and should be used instead of the simpler models in the case of application of the conventional well test analysis.

 References

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Keywords
well test analysis, composite reservoir, gravity override, heat loss, tilted front.