Session: 11-10-02 Development of Unconventional Reservoirs-2

Paper Number: 79249

79249 - A Novel Approach in Modelling Fluid Flow in Unconventional Reservoirs Incorporating Viscous, Inertial, Diffusion, Desorption and Advection Forces Contributions 

Well-known models such as Darcy's (incorporates viscous forces) and Forchheimer’s (combines viscous and inertial forces) have been a significant point of reference in predicting fluid flow in conventional reservoirs, but unfortunately, that’s not the case in unconventional reservoirs. This is mainly due to the extremely poor rock properties in unconventional reservoirs, which permitted other forces to become significant contributors when characterizing fluid flow behavior in unconventional reservoirs.

Diffusion, desorption, and advection forces are critical components and main contributors to fluid flow in unconventional reservoir. It predominates the nano scale, whereas it becomes less essential in macro and micro scales in which viscous and inertial forces effect becomes much more pronounced in these domains. Unfortunately, these forces contribution has been heavily underestimated when modeling fluid flow in the porous media, especially in tight unconventional reservoirs with a general agreement that viscous transport is the predominant controller.

The main motive behind this research is the necessity to develop a new model that characterizes fluid flow in macro, micro and nano domains by incorporating viscous, inertial, diffusion, desorption and advection forces. Although the effect of the mentioned forces has been investigated previously by many researchers, they studied the effect of such forces in general and unfortunately, did not create a model that can be used to reflect fluid flow in unconventional reservoirs.  Furthermore, the desire in this research is not to examine the effect of the five forces as transport mechanisms in any medium, rather we will focus on their effect in the porous media, more specifically tight reservoir rocks.

This work introduces a new comprehensive flow model suitable for tight unconventional reservoirs, including viscous, inertia, diffusion, desorption and advection forces, to account for fluid transport in the three scales. The new model addresses 1-D linear flow in tight unconventional reservoirs and has been mathematically derived and numerically solved using MATLAB software, and tested against a synthetic case study. Detailed parametric analysis to examine the effect of the permeability, density and viscosity on the newly derived model has been conducted, and very clear profiles and flow patterns of the main flow parameters were identified. It has been established that, with lower permeability of the porous medium and lower viscosity of the flowing fluid, diffusion, desorption and advection forces contribution becomes more predominant in controlling flow velocity. It should be noted that a thorough analysis was conducted to examine the effect of each term individually to optimize the efficiency of the newly created model The results of the newly derived equation that includes all five forces clearly depict the contribution of the three recently added mechanisms to the flow in the nano scaled pore spaces. Furthermore, a comparison between the suggested new model to existing models that are used in the field to describe the behavior of the flow in low permeability and low porous medium has been established.

Presenting Author: Mohammed Aldhuhoori Khalifa University of Science and Technology

Authors:

Mohammed Aldhuhoori Khalifa University of Science and Technology
Hadi Belhaj Khalifa University of Science and Technology
Bisweswar Ghosh Khalifa University of Science and Technology
Hamda Alkuwaiti Khalifa University of Science and Technology