High Differential Pressure, Radial Flow Characteristics of Gun Perforations

1985 ◽  
Author(s):  
J.A. Regalbuto ◽  
R.S. Riggs
Keyword(s):  
Radial Flow ◽  
Flow Characteristics ◽  
Differential Pressure

scholarly journals Bayesian Optimization Design of Inlet Volute for Supercritical Carbon Dioxide Radial-Flow Turbine

Machines ◽  
2021 ◽  
Vol 9 (10) ◽  
pp. 218
Author(s):  
Chao Bian ◽  
Shaojie Zhang ◽  
Jinguang Yang ◽  
Haitao Liu ◽  
Feng Zhao ◽  
...  
Keyword(s):  
Optimization Design ◽  
Radial Flow ◽  
Flow Characteristics ◽  
Bayesian Optimization ◽  
Working Fluid ◽  
Cross Sectional ◽  
Pressure Loss Coefficient ◽  
Flow Capacity ◽  
Cycle Efficiency ◽  
Total Pressure Loss Coefficient

The radial-flow turbine, a key component of the supercritical CO2 (S-CO2) Brayton cycle, has a significant impact on the cycle efficiency. The inlet volute is an important flow component that introduces working fluid into the centripetal turbine. In-depth research on it will help improve the performance of the turbine and the entire cycle. This article aims to improve the volute flow capacity by optimizing the cross-sectional geometry of the volute, thereby improving the volute performance, both at design and non-design points. The Gaussian process surrogate model based parameter sensitivity analysis is first conducted, and then the optimization process is implemented by Bayesian optimization (BO) wherein the acquisition function is used to query optimal design. The results show that the optimized volute has better and more uniform flow characteristics at design and non-design points. It has a smoother off-design conditions performance curve. The total pressure loss coefficient at the design point of the optimized volute is reduced by 33.26%, and the flow deformation is reduced by 54.55%.

Characteristics of Miniature Short-Tube Orifice Flows

1989 ◽  
Vol 203 (5) ◽  
pp. 351-358 ◽  
Author(s):  
T A Fox ◽  
J Stark
Keyword(s):  
Experimental Investigation ◽  
Critical Pressure ◽  
Fuel Injection ◽  
Flow Characteristics ◽  
Head Loss ◽  
Differential Pressure ◽  
Pressure Differential ◽  
Contraction Parameter ◽  
Volumetric Discharge ◽  
Short Tube

This paper presents the results of an experimental investigation into the flow characteristics of miniature short-tube orifices of a type commonly used for fuel injection. From measurements of differential pressure and volumetric discharge it is shown that these devices are susceptible to a cavitation-induced instability phenomenon known as hydraulic flip. It was found that this instability is limited to orifices of length less than fourteen diameters and occurs at a critical pressure differential which varies as a function of the orifice l/d ratio and contraction parameter β. In addition, the performance of the device is examined in terms of the head loss characteristics and it is shown that the mechanisms associated with hydraulic flip have a significant effect on the efficiency of discharge.

Study of Flow Characteristics of Oil and Water in the Process of Stirring

2013 ◽  
Vol 353-356 ◽  
pp. 3190-3193
Author(s):  
Zong Rui Hao ◽  
Juan Xu ◽  
Hai Yan Bie ◽  
Zhong Hai Zhou
Keyword(s):  
Flow Field ◽  
Flow Pattern ◽  
Cross Section ◽  
Radial Flow ◽  
Flow Characteristics ◽  
Stirred Tank ◽  
Turbulent Model ◽  
Vof Model ◽  
Circular Flows ◽  
Oil Water

To study the flow pattern in the process of oil-water stirring in three paddle stirring tank, RNG k-ε turbulent model and VOF model are adopted to simulate the flow field at different time in the stirred tank with the baffle. The results showed that, in the stirring process, inverted cone manifold was formed in the center of the stirring shaft. The stratified area was formed in the baffle and gradually transported to the bottom of the tank. The two circular flows were formed among three groups of blades. And the axially acting of the fluid was strong, which made homogeneous stirring in the stirred tank. At the same time the radial flow of the cross-section inside the tank increased because of the baffle.

scholarly journals Flow characteristics analysis of a two-phase suspension between rotating porous cylinders with radial and axial flows

2018 ◽  
Vol 22 (4) ◽  
pp. 1857-1864
Author(s):  
Yu-Chuan Zhu ◽  
Qing-He Xiao ◽  
Ming-Xin Gao ◽  
Qian Liu ◽  
Zhanhong Wan
Keyword(s):  
Reynolds Number ◽  
Stability Analysis ◽  
Radial Flow ◽  
Outer Cylinder ◽  
Flow Characteristics ◽  
Axial Flow ◽  
Taylor Number ◽  
Two Phase ◽  
Characteristics Analysis ◽  
Correlation Parameters

The flow characteristics problem of the two-phase suspension in the design of filters is presented, and the hydrodynamic stability is carried out to study the flow characteristics of a two-phase suspension between a rotating porous inner cylinder and a concentric, stationary, porous outer cylinder when radial flow and axial flow are present. Linear stability analysis results in an eigenvalue problem that is solved numerically by Wan?s method. The results reveal that the critical Taylor number for the onset of instability is altered by other parameters. For given correlation parameters, increasing the axial Reynolds number increases the critical Taylor number for transition very slightly, the critical Taylor number decreases as the axial Reynolds number becomes negative.

scholarly journals An Integrated Approach of Numerical Well Test for Well Intersecting Fractures Based on FMI Image

Lithosphere ◽  
2022 ◽  
Vol 2022 (Special 1) ◽  
Author(s):  
Guodong Jin ◽  
Huilin Xing ◽  
Tianbin Li ◽  
Rongxin Zhang ◽  
Junbiao Liu ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Radial Flow ◽  
Flow Characteristics ◽  
Integrated Approach ◽  
Unconventional Reservoirs ◽  
Well Test ◽  
Unconventional Reservoir ◽  
Transient Pressure ◽  
Drill Stem ◽  
Numerical Well Test

Abstract Fluid flow is strongly affected by fractures in unconventional reservoirs. It is essential to deeply understand the flow characteristics with fractures for improving the production and efficiency of unconventional reservoir exploitation. The purpose of this work is to develop an accurate numerical model to evaluate the transient-pressure response for well intersecting fractures. The meshes generated from Fullbore Formation Micro-Imager (FMI) images ensure an efficient numerical description of the geometries for fractures and interlayers. The numerical simulation is implemented by an inhouse finite element method-based code and benchmarked with drill stem test (DST) data. The results show that three flow regimes appear in the reservoir with fractures within the test period: wellbore afterflow, pseudolinear flow, and radial flow. In contrast, only the wellbore afterflow and radial flow appear for the wells without fractures. The results also reveal that fractures dominate the flow near the wellbore. Verification and application of the model show the practicability of the integrated approach for investigating the transient-pressure behaviors in the unconventional reservoir.

Flow Characteristics of a Centrifugal Pump

1994 ◽  
Vol 116 (2) ◽  
pp. 303-309 ◽  
Author(s):  
C. H. Liu ◽  
C. Vafidis ◽  
J. H. Whitelaw
Keyword(s):  
Refractive Index ◽  
Centrifugal Pump ◽  
Radial Flow ◽  
Flow Characteristics ◽  
Secondary Flows ◽  
Laser Doppler Velocimeter ◽  
Suction Surface ◽  
Tip Leakage ◽  
Tip Velocity ◽  
Working Liquid

Measurements of velocity have been obtained in a centrifugal pump in terms of angle-resolved values in the impeller passages, the volute, the inlet and exit ducts and are presented in absolute and relative frames. The pump comprised a radial flow impeller with four backswept blades and a single volute, and the working liquid had the same refractive index as the transparent casing to facilitate the use of a laser-Doppler velocimeter. The flows in the impeller passages were found to depart from the curvature of the blade surfaces at off-design conditions with separation from the suction surface and from the shroud. Secondary flows from the suction to pressure surfaces were dominated by the influences of the relative motion between the shroud and impeller surfaces and the tip leakage. Geometric differences of 0.5 mm and one degree in spacing of the four blades caused differences in passage velocity of up to 6 percent of the impeller tip velocity close to the design flowrate and up to 16 percent at the lowest discharge. The flowrate from each impeller passage varied with volute circumferential position by up to 25 percent at an off-design flowrate. Poor matching of the impeller and volute at off-design conditions caused swirl and separation in the inlet and exit pipes.

Transient Flow Characteristics of Low Permeability Gas Reservoirs and Improvement of Deliverability by Nuclear Explosion

1968 ◽  
Vol 8 (03) ◽  
pp. 209-223
Author(s):  
C. Kenneth Eilerts ◽  
Eudora F. Sumner
Keyword(s):  
Natural Gas ◽  
Radial Flow ◽  
Transient Flow ◽  
Nuclear Explosion ◽  
Flow Characteristics ◽  
Economic Feasibility ◽  
Low Permeability ◽  
Significant Variable ◽  
Reservoir Properties ◽  
Economic Significance

Abstract A program for computing the transient radial flow of natural gas, taking into account significant variable properties of the fluid and of the porous medium was used in an investigation of flow characteristics of formations for which the permeability-thickness product kh is 1 to 100 md-ft. A graphic summary of the results obtained may be used with well flow-test data to estimate kh for the formation in which the well is completed. Assuming that a nuclear explosion in a gas-containing formation would create a rubble-filled chimney with a diameter of 170 ft and fissures radiating from the chimney wall out to a distance of 255 ft, formation pressure gradients were computed for the recovery of gas with a well drilled into the chimney. These computations for 640-and 160-acre spacing indicate that diminution of the radius segment re - rf over which flow occurs in unaltered formation provides for markedly greater ultimate recovery of gas in place than is possible with conventional well completions. A formation drilled with conventional wells 1.0 mile apart must have a productivity product of kh = 197 md-ft to deliver for 20 years 1.0 MMscf/D of gas into a pipeline operated at 300 psi. Aided by nuclear stimulation, one well can meet the same performance requirements with a kh of only 49 md-ft for the native formation. With a spacing of 160 acres and nuclear stimulation, kh need be only 9 md-ft. Introduction Project Gasbuggy of the El Paso Natural Gas Co. and government agencies is concerned with the creation by nuclear explosion of a chimney and radiating fissures in a low-permeability formation containing natural gas. A well is to be drilled and completed in this chimney and tests will be made on this well and other wells in the vicinity to determine the economic feasibility of nuclear stimulation for recovery of the gas. Engineering studies of the Bureau of Mines pertaining to parts of this project have been in progress since 1963. Because of the complexity of the experiment, its cost, and possible economic significance, it is desirable to define the reservoir flow problem, determine by computing the relative importance of the parameters involved, and obtain a measure of the benefits that may be expected. The results should be generalized for application to other projects. Two parts of this problem have been investigated:determination of average properties of the native formation from flow tests of wells, andevaluation of the transient flow performance of a low-permeability formation in which a relatively high-permeability area has been created to receive a recovery well. Matthews and Russell have reviewed the difficulties of testing gas wells in low-permeability formations that stabilize slowly if at all, in this investigation a means was sought for using transient flow information obtained on such wells to determine reservoir properties, including the product kh. The investigation of nuclear stimulation was conducted with emphasis on determining what transient flow performance may be expected over the 20-year period of significance to gas producers. BASIC EQUATIONS The partial differential equation for transient radial flow of a gas phase, (1) was integrated in the range rd r re. With rd/re = 0.005 and 640-acre spacing rd = 14.9 ft, so that flow over most of the radius is computed by means of Eq. 1. A program previously described by the authors was used for this purpose. SPEJ P. 209ˆ

Sign in / Sign up

Export Citation Format

Share Document