scholarly journals Development of a three-dimensional model of the atmospheric boundary layer using the finite element method

1977 ◽  
Author(s):  
R.L. Lee ◽  
P.M. Gresho
Keyword(s):  
Boundary Layer ◽  
Finite Element Method ◽  
Finite Element ◽  
Atmospheric Boundary Layer ◽  
Three Dimensional ◽  
The Finite Element Method ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Element Method

scholarly journals Determination of hydraulic steam losses in the turbine control valve based on a three-dimensional model

Vestnik IGEU ◽  
2019 ◽  
pp. 12-23
Author(s):  
V.A. Gorbunov ◽  
N.A. Lonshakov ◽  
I.V. Alekseyev ◽  
M.N. Mechtayeva
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Steam Turbine ◽  
Three Dimensional ◽  
Control Valve ◽  
The Finite Element Method ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Hydraulic Losses ◽  
Measuring Devices

A problem to be solved now is determining the hub nodes of hydraulic losses arising during the operation of power plant equipment. Detection of such points directly by measuring devices on the operating equipment is impossible as it is difficult to access many elements of the flow part of the units. Development of digital models of equipment allows simulating these processes and with a high degree of accuracy determining the location of increased hydraulic losses. The aim of this work is to determine the magnitude and localization of hydraulic losses in the control valve of the steam turbine. The analysis of steam turbine valve operation has been carried out based on thermodynamic, hydraulic and mechanical parameters, which are taken directly during the operation of the power plant by standard control and measuring devices. The obtained information was processed by the finite element method in the Ansys and SolidEdge Flow Simulation programs and by three-dimensional modeling in the SolidEdge software package. We have obtained a three-dimensional model of the control valve and determined the fields of pressure, velocity, etc. distribution in the volume of the control valve under different operating conditions by the finite element method. During the processing of the obtained information, we found excessive energy losses of water vapor arising during its throttling in the control valve. Such losses produce a significant effect on the power developed by the turbine pump. During the operation of the drive turbine, the pressure losses of the working medium in the steam distribution system vary in the range of 300–500 kPa (37–62 % of the initial pressure before the control valve). The goal set in the work has been fully achieved. Verification of the developed three-dimensional model was made on the basis of the operational parameters taken during the steam turbine operation. The application of the work results, both for modernizing the existing units and designing new equipment, will increase the efficiency of electric energy production at the power unit of the station.

High-Speed Micromilling of Composite and Aluminum Alloy Parts

2021 ◽  
pp. 62-72
Author(s):  
E.V. Patraev ◽  
M.S. Vakulin ◽  
Y.I. Gordeev ◽  
V.B. Yasinsky
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
High Speed ◽  
Experimental Studies ◽  
Three Dimensional ◽  
The Finite Element Method ◽  
Three Dimensional Model ◽  
Workpiece Material ◽  
High Productivity ◽  
Element Method

The paper deals with the design of the cutting part of complex-profile cutters with high productivity and surface quality. Numerical experiments carried out using the finite element method made it possible to determine the stresses and strains in the layer of the cut material when machining with multifaceted milling cutters of a new type and indirectly estimate the specific cutting forces. The required dimensions and shape of the cutting wedge are set with account for various geometric parameters of the cutting part, properties of the workpiece material, and cutting conditions. This made it possible to obtain a three-dimensional model of an end mill with a trapezoidal tooth and 700 cutting edges. Experimental studies also showed a change in the morphology of chips with a size of about 2 microns, which is in good agreement with the results of preliminary estimates by the finite element method. The productivity of processing with milling cutters of a new design can be improved by increasing the number of single cutting cycles up to4000–6000 s–1.

Effect of Slit Structure of Purging Plug on Stress Field

2011 ◽  
Vol 418-420 ◽  
pp. 884-887 ◽  
Author(s):  
Xiao Xiao Huang ◽  
Wen Dong Xue ◽  
Jie Liu ◽  
Fa Han
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Stress Field ◽  
Boundary Conditions ◽  
Three Dimensional ◽  
Maximum Principal Stress ◽  
The Finite Element Method ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Length Width

The three-dimensional model of purging plug was analyzed by the finite element method. The influence of slit structure (length, width, center radius and numbers) on the maximum principal stress was Contrastive studied in argon blowing process under the same boundary conditions.

Front Car Door Modal Analysis Based on Finite Element Method

2011 ◽  
Vol 383-390 ◽  
pp. 7418-7421
Author(s):  
Li Sun ◽  
Yong Chen Liu
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Modal Analysis ◽  
Traffic Noise ◽  
Three Dimensional ◽  
The Finite Element Method ◽  
Three Dimensional Model ◽  
Vehicle Structure ◽  
The Right ◽  
Element Method

The car door modal analysis was an important method to obtain its dynamic characteristics. In order to analyze the natural frequency of the door, avoid resonance with the other vibration sources in the vehicle structure and reduce traffic noise, the right front door of a vehicle was made modal analysis based on the finite element method. First, the car door three-dimensional model was established in the CATIA, then it was imported into the HyperMesh to mesh, at last, imported into the Nastran, and the related settings was made to calculate the 7 modal frequencies of the door. By analysis of the vibration shape chart, the door low stiffness positions are found to provoid the reliable reference for optimizing the door design.

Towards Predicting Relative Belt Edge Endurance With the Finite Element Method

1990 ◽  
Vol 18 (4) ◽  
pp. 216-235 ◽  
Author(s):  
J. De Eskinazi ◽  
K. Ishihara ◽  
H. Volk ◽  
T. C. Warholic
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Three Dimensional ◽  
The Finite Element Method ◽  
Shear Deformations ◽  
Element Analysis ◽  
Vertical Loading ◽  
Predicted Values ◽  
Element Method

Abstract The paper describes the intention of the authors to determine whether it is possible to predict relative belt edge endurance for radial passenger car tires using the finite element method. Three groups of tires with different belt edge configurations were tested on a fleet test in an attempt to validate predictions from the finite element results. A two-dimensional, axisymmetric finite element analysis was first used to determine if the results from such an analysis, with emphasis on the shear deformations between the belts, could be used to predict a relative ranking for belt edge endurance. It is shown that such an analysis can lead to erroneous conclusions. A three-dimensional analysis in which tires are modeled under free rotation and static vertical loading was performed next. This approach resulted in an improvement in the quality of the correlations. The differences in the predicted values of various stress analysis parameters for the three belt edge configurations are studied and their implication on predicting belt edge endurance is discussed.

A Fluid-Structure Coupled Computational Framework for Fluid-Induced Failure and Fracture

2015 ◽  
Author(s):  
Patrick D. Lea ◽  
Charbel Farhat ◽  
Kevin G. Wang
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Extended Finite Element Method ◽  
Three Dimensional ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Extended Finite Element ◽  
Computational Framework ◽  
Fluid Structure ◽  
Fracture Models

This work extends and generalizes a recently developed fluid-structure coupled computational framework to model and simulate fluid-induced failure and fracture. In particular, a novel surface representation approach is proposed to represent a fractured fluid-structure interface in the context of embedded boundary method. This approach is generic in the sense that it is applicable to many different computational fracture models and methods, including the element deletion (ED) technique and the extended finite element method (XFEM). Two three-dimensional model problems are presented to demonstrate the salient features of the computational framework, and to compare the performance of ED and XFEM in the context of fluid-induced failure and fracture.

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