Numerical simulation of heat extraction performance in enhanced geothermal system with multilateral wells

This paper reviews basic results and recent developments in the field of small-scale gaseous hydrodynamics which has received significant attention in connection with small-scale science and technology. We focus on the modeling challenges arising from the breakdown of the Navier-Stokes description, observed when characteristic lengthscales become of the order of, or smaller than, the molecular mean free path. We discuss both theoretical results and numerical methods development. Examples of the former include the limit of applicability of the Navier-Stokes constitutive laws, the concept of second-order slip and the appropriate form of such a model, and how to reconcile experimental measurements of slipping flows with theory. We also review a number of recently developed theoretical descriptions of canonical nanoscale flows of engineering interest. On the simulation front, we review recent progress in characterizing the accuracy of the prevalent Boltzmann simulation method known as direct simulation Monte Carlo. We also present recent variance reduction ideas which address the prohibitive cost associated with the statistical sampling of macroscopic properties in low-speed flows.

http://absimage.aps.org/image/DFD05/MWS_DFD05-2005-020061.pdf

The limits of Navier-Stokes theory and kinetic extensions for describing small-scale gaseous hydrodynamics

Alkaline–surfactant–polymer (ASP) flooding is a combination process in which alkali, surfactant, and polymer are injected in the same slug. Because of the synergy of these three components, ASP is the current worldwide focus of research and field trial in chemical enhanced oil recovery (EOR).

This paper is to provide a comprehensive review of the ASP process. The reviewed topics include the following: 

ASP synergy and its EOR mechanisms
Screening criteria
Laboratory work
Numerical simulation work
Summary of pilots and large-scale applications
Project economics
Chemicals used
Water quality
Mobility control requirement
Problems associated with ASP flooding and possible solutions


In addition to the comprehensive review, future developments are also discussed. Data and analyzed results presented in this review will provide the reader with the updated information about ASP and a guide to read relevant papers for those who are new to chemical EOR. The survey data also provide operators with some reference data for their project design and optimization. © 2014 Curtin University of Technology and John Wiley & Sons, Ltd.

A comprehensive review of alkaline–surfactant–polymer (ASP) flooding

The adsorption behavior and underlying mechanism of CO2 and CH4 binary mixture in shale kerogen significantly affect the CO2 sequestration with enhanced gas recovery project (CS-EGR). In this study, we investigated the competitive adsorption behaviors of CO2 and CH4 in shale kerogen nanopores using grand canonical Monte Carlo (GCMC) method. Kerogen model takes into effect of matrix and slit nanopores and moisture content based on Ungerer’s molecular model and scanning electron microscope (SEM) analysis, and is successfully validated against experimental data. The effects of temperature, CO2 and CH4 distribution, moisture content, adsorption selectivity, and optimal formation for injection were discussed. The results show that adsorption amount of CH4 on the kerogen increases with increasing pressure and decreases with increasing temperature. The adsorption selectivity of CO2 over CH4 is 2.53–7.25, which indicates that CO2 is preferentially adsorbed over CH4 under different temperatures. H2O prefers to ads...

Molecular Simulation of CO2/CH4 Competitive Adsorption on Shale Kerogen for CO2 Sequestration and Enhanced Gas Recovery

A Comprehensive Review of Alkaline-Surfactant-Polymer (ASP) Flooding

A review of liquid nitrogen fracturing technology

Laboratory investigation on cryogenic fracturing of hot dry rock under triaxial-confining stresses

A complex fracture network is generally generated during the hydraulic fracturing treatment in shale gas reservoirs. Numerous efforts have been made to model the flow behavior of such fracture networks. However, it is still challenging to predict the impacts of various gas transport mechanisms on well performance with arbitrary fracture geometry in a computationally efficient manner. We develop a robust and comprehensive model for real gas transport in shales with complex non-planar fracture network. Contributions of gas transport mechanisms and fracture complexity to well productivity and rate transient behavior are systematically analyzed. The major findings are: simple planar fracture can overestimate gas production than non-planar fracture due to less fracture interference. A "hump" that occurs in the transition period and formation linear flow with a slope less than 1/2 can infer the appearance of natural fractures. The sharpness of the "hump" can indicate the complexity and irregularity of the fracture networks. Gas flow mechanisms can extend the transition flow period. The gas desorption could make the "hump" more profound. The Knudsen diffusion and slippage effect play a dominant role in the later production time. Maximizing the fracture complexity through generating large connected networks is an effective way to increase shale gas production.

/pdf/a-comprehensive-model-for-real-gas-transport-in-shale-1rr107al6l.pdf

Ruiyue Yang

Papers

Numerical simulation of heat extraction performance in enhanced geothermal system with multilateral wells

A review of liquid nitrogen fracturing technology

Laboratory investigation on cryogenic fracturing of hot dry rock under triaxial-confining stresses

A Comprehensive Model for Real Gas Transport in Shale Formations with Complex Non-planar Fracture Networks.

The self-propelled force model of a multi-orifice nozzle for radial jet drilling