scholarly journals Transient pressure behavior of horizontal well in gas reservoirs with arbitrary boundary

2020 ◽  
Vol 38 (6) ◽  
pp. 2370-2388
Author(s):  
Bo Ning ◽  
Jiafeng Xu ◽  
Jing Jiang ◽  
Minhua Cheng
Keyword(s):  
Horizontal Well ◽  
Outer Boundary ◽  
Production Performance ◽  
Critical Parameters ◽  
External Boundary ◽  
Inversion Method ◽  
Well Testing ◽  
Transient Pressure ◽  
Gas Reservoirs ◽  
Arbitrary Boundary

Transient pressure analysis is a crucial tool to forecast the production performance during the exploration and production process in gas reservoirs. Usually, a regular shaped outer boundary is assumed in previous studies for well-testing analysis, which is just a simplification of practical cases and cannot reflect the actual boundaries of reservoirs. In this paper, a mathematical model is established to analyze the transient pressure behaviors of a horizontal well in an arbitrarily shaped gas reservoir. Dimensionless treatment, Laplace transformation, and boundary element method are applied in solving the model, which is verified by comparing with the results from the source function method. Based on the Stehfest numerical inversion method, the models of single-porosity media and dual-porosity media are solved respectively. Then, the time-domain curves of pseudo pressure and its derivative are obtained, and the flow regimes are identified. Finally, the impacts of some critical parameters on pressure transient behaviors are analyzed, including storativity ratio, interporosity coefficient, well length, and well orientation. This paper presents an effective way to handle complex external boundary problems in gas reservoirs.

scholarly journals Effect of Geological Heterogeneity on the Production Performance of a Multifractured Horizontal Well in Tight Gas Reservoirs

Lithosphere ◽  
2021 ◽  
Vol 2021 (Special 1) ◽  
Author(s):  
Yue Peng ◽  
Tao Li ◽  
Yuxue Zhang ◽  
Yongjie Han ◽  
Dan Wu ◽  
...  
Keyword(s):  
Horizontal Well ◽  
Horizontal Wells ◽  
Gas Production ◽  
Production Performance ◽  
Tight Gas ◽  
Gas Reservoirs ◽  
Gas Reservoir ◽  
Tight Gas Reservoirs ◽  
Reservoir Permeability ◽  
Half Length

Abstract Multifractured horizontal wells are widely used in the development of tight gas reservoirs to improve the gas production and the ultimate reservoir recovery. Based on the heterogeneity characteristics of the tight gas reservoir, the homogeneous scheme and four typical heterogeneous schemes were established to simulate the production of a multifractured horizontal well. The seepage characteristics and production performance of different schemes were compared and analyzed in detail by the analysis of streamline distribution, pressure distribution, and production data. In addition, the effects of reservoir permeability level, length of horizontal well, and fracture half-length on the gas reservoir recovery were discussed. Results show that the reservoir permeability of the unfractured areas, which are located at both ends of the multifractured horizontal well, determines the seepage ability of the reservoir matrix, showing a significant impact on the long-term gas production. High reservoir permeability level, long horizontal well length, and long fracture half-length can mitigate the negative influence of heterogeneity on the gas production. Our research can provide some guidance for the layout of multifractured horizontal wells and fracturing design in heterogeneous tight gas reservoirs.

Flow Modeling of Well Test Analysis for a Multiple-fractured Horizontal Well in Triple Media Carbonate Reservoir

2018 ◽  
Vol 19 (5) ◽  
pp. 439-457 ◽  
Author(s):  
Yong Wang ◽  
Xiangyi Yi
Keyword(s):  
Horizontal Well ◽  
Outer Boundary ◽  
Superposition Principle ◽  
Horizontal Wells ◽  
Carbonate Reservoir ◽  
Well Test ◽  
Transient Pressure ◽  
Well Test Analysis ◽  
Fractured Horizontal Well ◽  
Fractured Horizontal Wells

AbstractCarbonate reservoir is one kinds of important reservoir in the world. Because of the characteristics of carbonate reservoir, horizontal well, and acid fracturing became a key technology for efficiently developing carbonate reservoir. Establishing corresponding mathematical models and analyzing transient pressure behaviors of this type of well-reservoir configuration can provide a better understanding of fluid flow patterns in formation as well as estimations of important parameters. A coupling mathematical model for a fractured horizontal well in triple media carbonate reservoir with three kinds of reservoir outer boundaries by conceptualizing vugs as spherical shapes is presented in this article, in which the infinite conductivity of the acid fractures is taken into account. A semi-analytical solution is obtained in the Laplace domain by using source function theory, Laplace transformation, discretization of fracture, and superposition principle. Analysis of transient pressure responses indicates that several characteristic flow periods of fractured horizontal wells in triple media carbonate reservoir can be identified. Parametric analysis shows that fracture half-length, fracture number, fracture spacing, conditions of reservoir outer boundary, and so on can significantly influence the transient pressure responses of fractured horizontal wells in triple media carbonate reservoir. The model presented in this article can be applied to obtain important parameters pertinent to reservoir or fracture by type curve matching, and it can also provide useful information for optimizing fracture parameters.

scholarly journals Diagnosis of Water-Influx Locations of Horizontal Well Subject to Bottom-Water Drive through Well-Testing Analysis

Geofluids ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-14
Author(s):  
Jiazheng Qin ◽  
Shiqing Cheng ◽  
Youwei He ◽  
Dingyi Li ◽  
Le Luo ◽  
...  
Keyword(s):  
Oil Recovery ◽  
Horizontal Well ◽  
Bottom Water ◽  
Well Testing ◽  
Transient Pressure ◽  
Type Curves ◽  
Water Influx ◽  
Water Breakthrough ◽  
Production Distribution ◽  
Anisotropic Reservoir

Horizontal well (HW) has been widely applied to enhance well productivity and prevent water coning in the anisotropic reservoir subject to bottom-water drive. However, the water-cut increases quickly after only one or two years’ production in China while oil recovery still keeps at a very low level. It becomes a major challenge to effectively estimate production distribution and diagnose water-influx locations. Ignoring the effect of nonuniform production distribution along wellbore on pressure response may cause erroneous results especially for water-influx location determination. This paper developed an analytical method to determine nonuniform production distribution and estimate water-influx sections through well-testing analysis. Each HW is divided into multiple producing segments (PS) with variable parameters (e.g., location, production, length, and skin factor) in this model. By using Green’s functions and the Newman-product method, the novel transient pressure solutions of an HW can be obtained in the anisotropic reservoir with bottom-water drive. Secondly, the influences of nonuniform production-distribution on type curves are investigated by comparing the multisegment model (MSM) with the whole-segment model (WSM). Results indicate that the method proposed in this paper enables petroleum operators to interpret parameters of reservoir and HW more accurately by using well-testing interpretation on the basis of bottom-hole pressure data and further estimate water-influx sections and nonproducing segments. Additionally, relevant measures can be conducted to enhance oil production, such as water controlling for water-breakthrough segments and stimulation treatments for nonproducing locations.

The Dual-Porosity Vertical-Well Model for Transient Pressure Analysis of Naturally Fractured Shale Gas Reservoirs

2013 ◽  
Vol 448-453 ◽  
pp. 3958-3962
Author(s):  
Yi Jiang ◽  
Rui Xu ◽  
Meng Chen
Keyword(s):  
Shale Gas ◽  
Stress Sensitivity ◽  
Dual Porosity ◽  
Well Testing ◽  
Algebraic Equations ◽  
Transient Pressure ◽  
Gas Reservoirs ◽  
Shale Gas Reservoirs ◽  
Transient Pressure Analysis ◽  
Numerical Well Testing

During the process of development for shale gas reservoirs, the permeability of fractures will decrease due to stress-sensitive effect. Adsorption is also an important mechanism which determines the production of shale gas reservoirs. Therefore, the effect of stress sensitivity and adsorption must be considered in the numerical model for pressure transient analysis. In this paper, a dual-porosity model was established considering both mechanisms, and finite-difference method was used for discretizing fluid equations. Then Newton method was applied for solving the resulting algebraic equations, and the typical curves in terms of dimensionless pseudopressure and time were drawn with different sets of parameters. The numerical well-testing model provides theoretical basis for interpreting production data of shale gas reservoirs.

Sign in / Sign up

Export Citation Format

Share Document