scholarly journals Bathtub Vortex Profile and Flow Field Model with Circulation.

1998 ◽  
Vol 64 (620) ◽  
pp. 972-978 ◽  
Author(s):  
Seigo SAKAI ◽  
Haruki MADARAME ◽  
Koji OKAMOTO
Keyword(s):  
Flow Field ◽  
Field Model ◽  
Bathtub Vortex

Simulation of Gap Flow Field in EDM Process Uesd Oil-in-Water Working Fluid

2020 ◽  
Vol 841 ◽  
pp. 232-237
Author(s):  
Wei Jie Chang ◽  
Yan Ying Xi ◽  
Hao Wei Li
Keyword(s):  
Flow Field ◽  
Field Model ◽  
Corrosion Products ◽  
Working Fluid ◽  
Electrical Discharges ◽  
Electric Discharge Machining ◽  
Processing Depth ◽  
Gap Flow ◽  
Oil In Water ◽  
Edm Process

Electric Discharge Machining (EDM) working fluid as a medium can control electrical discharges occur, carry away the heat, compress discharge channel and help remove the corrosion products out of the gap. The main working fluids used in EDM are oil-based working fluid, gas-based working fluid, powder mixed working fluid, gas mixed working fluid and water-based working fluid. In order to improve the green and safety of EDM working fluid, an oil-in-water working fluid is proposed. A gap flow field model of EDM is established by using external flushing fluid. The flow field distribution, pressure distribution and corrosion products distribution of the machining gap are analyzed by using computational fluid dynamics. The effects of inlet pressure, processing depth and electrode size on the flow field are studied. The simulated results show that within a certain range, removal effect of the corrosion products will increase with inlet velocity and the size of electrode and decrease with processing depth.

Automotive Hydraulic Valve Fluid Field Estimator Based on Non-Dimensional Artificial Neural Network (NDANN)

2003 ◽  
Author(s):  
M. Cao ◽  
K. W. Wang ◽  
L. DeVries ◽  
Y. Fujii ◽  
W. E. Tobler ◽  
...  
Keyword(s):  
Neural Network ◽  
Control System ◽  
Flow Field ◽  
Flow Rate ◽  
Field Model ◽  
Operating Conditions ◽  
Asymmetric Flow ◽  
Fluid Force ◽  
Fluid Field ◽  
Hydraulic Valve

A conventional automatic transmission (AT) hydraulic control system includes many spool-type valves that have highly asymmetric flow geometry. An accurate analysis of their flow fields typically requires a time-consuming computational fluid dynamics (CFD) technique. A simplified flow field model that is based on a lumped geometry is computationally efficient. However, it often fails to account for asymmetric flow characteristics, leading to an inaccurate analysis. In this work, a new hydraulic valve fluid field model is developed based on a non-dimensional neural network (NDANN) to provide an accurate and numerically efficient tool in AT control system design applications. A “grow-and-trim” procedure is proposed to identify critical non-dimensional inputs and optimize the network architecture. A hydraulic valve testing bench is designed and built to provide data for neural network model development. NDANN-based fluid force and flow rate estimator are established based on the experimental data. The NDANN models provide more accurate predictions of flow force and flow rates under broad operating conditions compared with conventional lumped flow field models. The NDANN fluid field estimator also exhibits input-output scalability. This capability allows the NDANN model to estimate the fluid force and flow rate even when the design geometry parameters are outside the range of the training data.

Numerical modeling and experimental investigation of fiber diameter of melt blowing nonwoven web

2015 ◽  
Vol 27 (1) ◽  
pp. 91-98 ◽  
Author(s):  
Bo Zhao
Keyword(s):  
Flow Field ◽  
Field Model ◽  
Fiber Diameter ◽  
Jet Flow ◽  
Experimental Result ◽  
Computer Assisted ◽  
Melt Blowing ◽  
Content Type ◽  
Air Jet ◽  
Computer Assisted Design

Purpose – The purpose of this paper is to varify, the air drawing model and the air jet flow field model of dual slot shape die for a polymer in a melt blowing process were established, by the experimental results obtained with experimental equipment. Design/methodology/approach – The air jet flow field model is solved by introducing the finite difference method. The air drawing model of polymers in the melt blowing process was studied with the help of the simulation results of the air jet flow field. Findings – The higher air initial velocity and air initial temperature can all yield finer fibers and causes the fibers to be attenuated to a greater extent. Originality/value – The predicted fiber diameter agrees well with the experimental result, which verifies the reliability of these models. At the same time, the results also reveal the great potential of this research for the computer-assisted design of melt blowing technology.

Simulation and Experimental Investigations of Fiber Diameter of Spunbonding Nonwovens by Means of the Air Jet Flow Field Model

2010 ◽  
Vol 136 ◽  
pp. 5-9
Author(s):  
B. Zhao
Keyword(s):  
Experimental Data ◽  
Flow Field ◽  
Particle Image ◽  
Field Model ◽  
Fiber Diameter ◽  
Jet Flow ◽  
Experimental Investigations ◽  
Air Velocity ◽  
Air Jet ◽  
Image Velocimetry

The air jet flow field models of spunbonding process are founded. It is simulated by means of the finite difference method. The numerical simulation computation results of distributions of the air velocity match quite well with the experimental data. The air drawing model of polymer is solved with the help of the distributions of the air velocity measured by a particle image velocimetry. The predicted filament fiber diameter agrees with the experimental data well.

Synthetic Flow-Field Analysis of Main and Auxiliary Nozzles in Air-Jet Looms

2011 ◽  
Vol 411 ◽  
pp. 16-20 ◽  
Author(s):  
Shuan Jun Song ◽  
Dan Feng Shen
Keyword(s):  
Flow Field ◽  
Total Pressure ◽  
Field Model ◽  
Field Analysis ◽  
Comparison Analysis ◽  
Air Jet ◽  
Before And After ◽  
Flow Field Analysis ◽  
Air Jet Loom ◽  
First Time

The synthetic flow-field model of main and auxiliary nozzle flow-field in air-jet loom is introduced. The software of computational fluid dynamics FLUENT is used for the first time to simulate synthetic flow-field, and velocity vector is analyzed. To different spray angles of auxiliary nozzle, the velocity and total pressure of central air are compared in brief. The boundary conditions are changed by User Defined Functions (UDF) and the comparison analysis is done before and after using UDF.

scholarly journals An Independent-Flow-Field Model for a SDOF Nonlinear Structural System–Part II: Analysis of Complex Responses

2005 ◽  
Vol 128 (1) ◽  
pp. 23-30 ◽  
Author(s):  
Huan Lin ◽  
Solomon C. S. Yim
Keyword(s):  
Flow Field ◽  
Field Model ◽  
Periodic Wave ◽  
Experimental Results ◽  
Experimental Result ◽  
Structural System ◽  
Frequency Domains ◽  
Wave Heights ◽  
System Part ◽  
Good Agreement

Complex responses observed in an experimental, nonlinear, moored structural system subjected to nearly periodic wave excitations are examined and compared to the simulations of a newly proposed independent-flow-field (IFF) model in this paper. Variations in wave heights are approximated by additive random perturbations to the dominant periodic component. Simulations show good agreement with the experimental results in both time and frequency domains. Noise effects on the experimental results, including bridging and transition phenomena, are investigated and interpreted by comparing to the simulations of its deterministic counterpart. Possible causes of a chaoticlike experimental result as previously observed are also inferred.

scholarly journals An Independent-Flow-Field Model for a SDOF Nonlinear Structural System: Part II — Analysis of Complex Responses

2003 ◽  
Author(s):  
Huan Lin ◽  
Solomon C. S. Yim
Keyword(s):  
Flow Field ◽  
Field Model ◽  
Periodic Wave ◽  
Experimental Results ◽  
Experimental Result ◽  
Structural System ◽  
Frequency Domains ◽  
Wave Heights ◽  
System Part ◽  
Good Agreement

Complex responses observed in an experimental, nonlinear, moored structural system subjected to nearly periodic wave excitations are examined and compared with the simulations of a newly proposed independent-flow-field (IFF) model in this paper. Variations in wave heights are approximated by additive random perturbations to the dominant periodic component. Simulations show good agreement with the experimental results in both time and frequency domains. Noise effects on the experimental results including bridging and transition phenomena are investigated and interpreted by comparing with the simulations of its deterministic counterpart. Possible causes of a chaotic-like experimental result as previously observed are also inferred.

scholarly journals Steady-State Flow Characteristics and End Clearance Optimization of Internal Gear Grease Pump

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Xinjian Li ◽  
Lingfeng Tang ◽  
Ming Qian
Keyword(s):  
Flow Field ◽  
Field Model ◽  
Flow Characteristics ◽  
High Viscosity ◽  
Effect Of Temperature ◽  
Working Pressure ◽  
Side Plate ◽  
Clearance Flow ◽  
Fluent Software ◽  
Internal Gear

The internal gear grease pump is a mechanical device used for transfer of high viscosity fluid. The existing clearance between the end faces of the internal or external gear and the floating side plate might cause pump leakage during operation. In order to obtain the optimal end clearance of the internal gear grease pump, the rheological features of the lubricating lithium-based grease for various temperatures are explored via rotating rheometer. Shear force and apparent viscosity are chosen as monitored experimental parameters. The experimental data is fitted to obtain grease rheological features at various temperatures. The end clearance flow field model and the leakage model are established. Fluent software is employed for solving the flow field model and exploring the effect of temperature, end clearance, and speed on grease leakage. Superior grease flow performance is observed with an increase in temperature, which makes it to easier for the grease to leak from the end clearance. With an increase in the end clearance and the working pressure of the pump, an increase in leakage is also observed. Furthermore, it is found that rotational speed also affects the pump leakage. The leakage mechanism is obtained by combining the rheological features of the grease at the end clearance. The mathematical model method is utilized to solve for the optimal value of the end clearance.

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