Influences of fluid property variation on the boundary layers of a stretching surface

Summary Significant fluid-property variation can be induced with pressure and temperature dynamics in the reservoir associated with oil production. The existing analytical solutions for temperature-transient analysis (TTA) generally assume constant fluid properties, which can be invalid especially for cases of high drawdown and strong temperature signals. In this study, we present a method to account for the fluid-property variations in TTA. The method introduces corrections on fluid-property values as input for analytical solutions, considering the quasilinear behavior of the temporal Joule-Thomson effect on a semilog plot. The corrections are performed on four identified fluid properties in an iterative manner, which can be easily implemented in available temperature-analysis procedures. To validate the developed approach, we model drawdown- and buildup-transient-temperature signals with the fluid-property correction method for nondamaged and damaged reservoirs under different production rates and reservoir-fluid compositions. The analytical modeling results are compared with numerical simulations. In addition, by finding the dominating fluid property, a simplified approach of property correction is presented. Through application to example problems, we show that using the fluid-property correction method presented here can improve the permeability estimations by 60% for the conditions considered in this paper. We present a modified method for damaged reservoirs, which results in an additional 25% improvement on the permeability estimations. With these improvements, the applicability of TTA using analytical solutions can be extended from cases with limited sandface-temperature signals of a few degrees Celsius to stronger signals of 20 to 30°C.

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SYMMETRY CLASSIFICATION OF NEWTONIAN INCOMPRESSIBLE FLUID'S EQUATIONS FLOW IN TURBULENT BOUNDARY LAYERS

Ciência e Natura ◽

10.5902/2179460x18067 ◽

2016 ◽

Vol 38 (2) ◽

pp. 745

Author(s):

Elham Dastranj

Keyword(s):

Symmetry Group ◽

Boundary Layers ◽

Turbulent Boundary Layers ◽

Group Method ◽

Stretching Surface ◽

Group Invariant ◽

Levi Decomposition ◽

Flow And Heat Transfer ◽

Group Invariant Solutions

Lie-group method is applicable to both linear and nonlinear partial dierential equations, which leads to nd new solutions for partial dierential equations. Lie symmetry group method is applied to study Newtonian incompressible uid’s equations ow in turbulent boundary layers. (Flow and heat transfer of an incompressible viscous uid over a stretching sheet appear in several manufacturing processes of industry such as the extrusion of polymers, the cooling of metallic plates, the aerodynamic extrusion of plastic sheets, etc. In the glass industry, blowing, oating or spinning of bres are processes, which involve the ow due to a stretching surface.) The symmetry group and its optimal system are given, and group invariant solutions associated to the symmetries are obtained [9, 10]. Finally the structure of the Lie algebra such as Levi decomposition, radical subalgebra, solvability and simplicity of symmetries is given.

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