Field Investigation of Heat Transfer in Hydraulic Fractures and the Effect of Heat Transfer on Fracturing Fluid Design

1996 ◽  
Author(s):  
David P. Craig ◽  
Ted D. Brown ◽  
John W. Ely
Keyword(s):  
Heat Transfer ◽  
Field Investigation ◽  
Hydraulic Fractures ◽  
Fracturing Fluid ◽  
Fluid Design

Controlling the Height of Multiple Hydraulic Fractures in Layered Media

SPE Journal ◽  
2016 ◽  
Vol 21 (01) ◽  
pp. 256-263 ◽  
Author(s):  
Aditya Khanna ◽  
Andrei Kotousov
Keyword(s):  
Fluid Pressure ◽  
Pressure Control ◽  
Shielding Effect ◽  
Hydraulic Fractures ◽  
Fracturing Fluid ◽  
Fracture Spacing ◽  
Gas Recovery ◽  
Fracture Opening ◽  
Fracture Height ◽  
Fracture Height Containment

Summary Fracture-height containment is desirable in hydraulic-fracturing treatments because it can result in better efficiency of oil or gas recovery and have less impact on the environment. Several mechanisms of the containment of a single hydraulic fracture were investigated in the past, and the outcomes of these studies are now well-documented in the open literature. However, the effectiveness of these mechanisms in the case of multiple closely spaced hydraulic fractures has not received much attention. The latter situation typically arises in the case of multiple transverse fractures emanating from a single horizontal wellbore. In this paper, we develop a mathematical model that one can use to assess the fracture-interaction phenomenon as well as the effect of the modulus contrast between adjacent rock layers. We consider the situation in which one must contain the hydraulic fractures entirely in the pay zone and investigate fracturing-fluid-pressure control as a possible mechanism of height containment. It is demonstrated that when the fracture spacing becomes comparable with the fracture height, the interaction between the fractures produces a shielding effect. In this case, the fracturing-fluid pressure that ensures fracture containment is greater in comparison with the case of a single isolated fracture. However, the fracture opening is also smaller in the case of closely spaced fractures. The dependence of the fracturing-fluid pressure and fracture opening on the fracture spacing needs to be taken into consideration during the selection of fracture spacing for a particular treatment.

Impediments to Refracturing Success in Shale Reservoirs

2021 ◽  
Author(s):  
Clay Kurison
Keyword(s):  
Hyperbolic Equation ◽  
Reservoir Simulation ◽  
Analytical Techniques ◽  
Horizontal Wells ◽  
B Value ◽  
Hydraulic Fractures ◽  
Fracturing Fluid ◽  
Minimal Impact ◽  
Wellhead Pressure ◽  
The Matrix

Abstract Stimulations in early horizontal wells in most shale plays are characterized by few and widely spaced perforation clusters, and low amounts of injected fracturing fluid and proppant. Low recovery from these wells has motivated refracturing although outcomes have been interpreted to range from successful to minimal impact based on operator specific evaluations. To tailor available technologies and improve quantification of upsides, there is need for mapping the spatial distribution of remaining resources and developing simpler but reliable analytical techniques. In this study, hydraulic fractures were assumed to be planar in a matrix with low porosity and ultra-low permeability. Consideration of natural fractures and their interaction with stimulation fluids led to addition of distributed fracture networks adjacent to the planar hydraulic fractures to define the composite fracture corridors. A sector model with the aforementioned architecture was used in reservoir simulation to investigate induced temporal and spatial drainage. These findings were used to explain the efficacy of widely used refracturing techniques and how post-refracturing reservoir response can be analyzed. Results from reservoir simulation showed remaining reserves were in the matrix between earlier placed hydraulic fractures aligned along initial perforation clusters, and beyond tips of hydraulic fractures. Upside from refracs could come from creation of new fractures in the matrix between earlier placed fractures and extension of tips of early fractures into virgin matrix. Assessment of these scenarios found the former to be optimal although depletion and existing perforations would limit the stimulation efficiency of new perforations. The second scenario would require large volumes of fracturing fluid to re-initiate fracture propagation. Yet this could trigger interference with offsets or affect drilling and stimulation of planned wells in adjacent acreage. For treatment efficiency, re-casing horizontal wells with competent liners and use of coiled tubing with straddle packers appears a better solution for bypassing old perforations. For the near wellbore and far field, re-stimulating new perforations at low injection rates could allow extension of fractures in virgin matrix surrounded by depleted strata. Real-time surveillance would be essential for mapping flow paths of refracturing fluid. For assessment of refracturing, actual and simulated flow exhibited persistent linear flow (PLF) that could be matched by Arps hyperbolic equation with a b value of 2. Incorporation of a novel fracture geometry factor (FGF) yielded an Arps-based equation that was tested on North American shale refracturing cases that often use post-treatment peak rate and wellhead pressure as measures of success. This study identified factors hindering the success of refracturing and proposed a modified Arps hyperbolic equation to analyze refracturing production data.

scholarly journals Field investigation on heat transfer in an urban canyon.

1990 ◽  
Vol 56 (524) ◽  
pp. 1155-1160
Author(s):  
Atsumasa YOSHIDA ◽  
Kazuhide TOMINAGA ◽  
Shigeru WATATANI
Keyword(s):  
Heat Transfer ◽  
Field Investigation ◽  
Urban Canyon

Hybrid Analytical/Numerical Computation of Heat Transfer in a Gas-Driven Fracture

1986 ◽  
Vol 108 (3) ◽  
pp. 585-590 ◽  
Author(s):  
S. K. Griffiths ◽  
R. H. Nilson ◽  
F. A. Morrison
Keyword(s):  
Heat Transfer ◽  
Surrounding Medium ◽  
Numerical Procedure ◽  
Early Time ◽  
Similarity Solutions ◽  
Fixed Number ◽  
Coupled Processes ◽  
Hydraulic Fractures ◽  
Rock Blasting ◽  
Fracture Growth

In gas-driven hydraulic fractures, as occur in rock blasting and underground nuclear testing, the high-temperature gases (1000 to 30,000 K) are radically cooled by heat transfer to the host material. This significantly reduces both the maximum extent and rate of fracture growth. The coupled processes of fluid flow, heat transfer, and rock deformation governing fracture growth are calculated here by a hybrid analytical/numerical procedure. The gas motion along a fracture of increasing length and aperture is described by a finite-difference form of the one-dimensional transport equations; fluid friction, advective heat transfer, and heat loss to the walls of the fracture are considered. Lateral heat losses are evaluated in a quasi-analytical fashion, based on an integral method that accounts for the convective film resistance between the fluid and fracture wall, as well as the conductive resistance within the surrounding medium. The calculations are performed on a difference grid that expands to maintain a fixed number of points uniformly distributed along the fracture. The present numerical results agree, within appropriate limits, with known similarity solutions. Beyond this, new nonsimilar solutions for early-time fracture growth are presented.

Consequences of Fracturing Fluid Lag in Three-Dimensional Hydraulic Fractures

1993 ◽  
Author(s):  
S.H. Advani ◽  
T.S. Lee ◽  
R.H. Dean ◽  
C.K. Pak ◽  
J.M. Avasthi
Keyword(s):  
Three Dimensional ◽  
Hydraulic Fractures ◽  
Fracturing Fluid ◽  
Fluid Lag

Effect of Uneven Wall Heating Conditions Under Different Buoyancy Numbers for a One Side Rib-Roughened Rotating Channel

2017 ◽  
Vol 139 (11) ◽  
Author(s):  
Zhi Wang ◽  
Roque Corral
Keyword(s):  
Heat Transfer ◽  
Flow Field ◽  
Field Investigation ◽  
Numerical Results ◽  
Navier Stokes ◽  
Wall Heating ◽  
Uneven Heating ◽  
A Minor ◽  
Rotating Channel ◽  
Heated Case

This paper investigates the impacts of uneven wall heating conditions under different buoyancy numbers on flow field and heat transfer performance of a rotating channel with one side smooth and one side roughened by 45 deg inclined ribs. Parametric Reynolds-averaged Navier–Stokes (RANS) simulations were conducted under two different wall heating conditions: only ribbed wall heated, as in experiment setup, and all walls heated, under three different buoyancy numbers. Results are compared, when available, with experimental results. Numerical results show that uneven wall heating has only a minor impact on nonrotating cases and very low buoyancy rotating cases. However, it has a significant influence, on both, the heat transfer behavior and the flow field, when the buoyancy number is large. In the ribbed trailing rotating tests, the all walls heated cases show significantly higher heat transfer rate than only the ribbed wall heated cases. The discrepancy is enlarged as buoyancy number increases. The heat transfer in the all walls heated case increases monotonically with the buoyancy number, whereas in the ribbed wall, heated case is slight reduced. In the ribbed leading rotating tests, the heat transfer sensitivity to the heating conditions is not conspicuous, and for both cases, the heat transfer level slightly reduced as the buoyancy number increased. The flow field investigation shows that there is a significant displacement of main flow in the all walls heated cases than only the ribbed wall heated cases under high buoyancy numbers. This displacement is due to the buoyancy effect and responsible for the heat transfer differences in uneven heating problems. According to the results obtained in the paper, we conclude that when buoyancy effects are relevant, the heating settings can play a significant role in the heat transfer mechanisms and therefore in the experimental and numerical results.

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