Iterative eigenvalue analysis for stability design of three-dimensional frames considering a fictitious axial force factor

2010 ◽  
Vol 10 (4) ◽  
pp. 325-335 ◽  
Author(s):  
Dong-Ho Choi ◽  
Ho-Sung Na ◽  
Jin-Woo Jung ◽  
Hoon Yoo
Keyword(s):  
Axial Force ◽  
Three Dimensional ◽  
Eigenvalue Analysis ◽  
Force Factor

Numerical Investigation of the Effect of Balancing-Hole on the Axial Force of a Partial Emission Pump

2014 ◽  
Author(s):  
Zhang Lisheng ◽  
Jiang Jin ◽  
Xiao Zhihuai ◽  
Li Yanhui
Keyword(s):  
Axial Force ◽  
Stokes Equations ◽  
Dominant Role ◽  
Three Dimensional ◽  
Navier Stokes ◽  
Design Parameters ◽  
Navier Stokes Equations ◽  
Computational Fluid Dynamics Cfd ◽  
The Cost

In this paper numerical simulations were conducted to analyze the effects of design parameters and distribution of balancing-hole on the axial-force of a partial emission pump. The studied pump is a single stage pump with a Barske style impeller. Based on the original impeller, we designed 7 pumps with different balancing-hole diameters and the partial emission pump equipped with different impellers were simulated employing the commercial computational fluid dynamics (CFD) software Fluent 12.1 to solve the Navier-Stokes equations for three-dimensional steady flow. A sensitivity analysis of the numerical model was performed with the purpose of balancing the contradiction of numerical accuracy and the cost of calculation. The results showed that, with increasing of the capacity, the axial force varies little. The diameter of the inner balancing-hole plays a dominant role of reducing axial-force of partial emission pump, the axial-force decreases with increasing of inner balancing-hole diameter on the whole range of operation, the axial-force of impeller without inner balancing-hole is approximately 3 times larger than that of impeller with inner balancing-hole. While the diameter of outer balancing-hole has a reverse effects compared with that of inner balancing-hole. With increasing of outer balancing-hole, the axial force increases accordingly.

scholarly journals Numerical analysis of symmetrical and asymmetrical reinforced concrete flat slabs - an integrated slab/ column analysis

2016 ◽  
Vol 9 (3) ◽  
pp. 306-356
Author(s):  
A. Puel ◽  
D. D. Loriggio
Keyword(s):  
Numerical Analysis ◽  
Axial Force ◽  
Three Dimensional ◽  
Bending Moment ◽  
Bending Moments ◽  
Flat Slabs ◽  
Distributed Load ◽  
Significant Difference ◽  
Local Support ◽  
Internal Forces

ABSTRACT This paper studies the modeling of symmetric and asymmetric flat slabs, presenting alternatives to the problem of singularity encountered when the slab is modeled considering columns as local support. A model that includes the integrated slab x column analysis was proposed, distributing the column reactions under the slab. The procedure used transforms the bending moment and column axial force in a distributed load, which will be applied to the slab in the opposite direction of gravitational loads. Thus, the bending moment diagram gets smooth in the punching region with a considerable reduction of values, being very little sensible to the variation of used mesh. About the column, it was not seen any significant difference in the axial force, although the same haven't occurred with the bending moments results. The final part of the work uses geoprocessing programs for a three-dimensional view of bending moments, allowing a new comprehension the behavior of these internal forces in the entire slab.

EVALUATION FOR RESIDUAL AXIAL FORCE OF CORRODED HIGH TENSILE BOLTS

2014 ◽  
Vol 1 (1) ◽  
Author(s):  
Ryoichi Satake ◽  
Katashi Fujii ◽  
Yumi Mori
Keyword(s):  
Axial Force ◽  
Three Dimensional ◽  
High Strength ◽  
Surface Shape ◽  
Thickness Reduction ◽  
Long Time ◽  
Force Reduction ◽  
The Relationship ◽  
Dimensional Surface

This paper presents a method for evaluating the residual axial force of corroded high strength bolts in experiments, and analysis measuring the axial force of corroded high strength bolts. In order to reproduce the axial force reduction due to corrosion, the test specimens were made by cutting the bolt head widthwise or the height-wise with an initial axial force. The curve of axial force lowering is prepared with a reduced thickness in height and width of bolts as a parameter. Therefore, the residual axial force can be estimated by the thickness reduction of bolt. Moreover, we measured the residual axle force of real corroded high strength bolts, taken from a bridge removed from service for a long time, and inspected an axis drop curve. In order to classify corrosion shapes, we measured the three-dimensional surface shape of corroded high strength bolts without contact, and considered the relationship between the surface shape of corroded high strength bolts and the axial force reduction.

Loosening Resistance Evaluation of Double-Nut Tightening Method, Spring Washers, and Conical Spring Washers: Finite Element Study

2008 ◽  
Author(s):  
Takashi Yokoyama ◽  
Satoshi Izumi ◽  
Shinsuke Sakai
Keyword(s):  
Finite Element ◽  
Axial Force ◽  
Rotation Angle ◽  
Three Dimensional ◽  
Bearing Surface ◽  
Surface Slip ◽  
Dimensional Finite Element ◽  
Negative Effect ◽  
Three Dimensional Finite Element ◽  
Positive Effect

The mechanisms of loosening resistance components are investigated within the framework of the three-dimensional finite element method (FEM). Here, the results of the double-nut tightening method (DN), spring washers (SW), and conical spring washers (CSW) are shown. This paper focuses on the comparison among the components above based on the results that have been published separately. For details on each analysis, readers are referred to [10–12]. We have found that DN shows significant loosening resistance if the locking is properly realized in the tightening process. However, if the locking is not performed properly, its ability to resist loosening completely disappears. SW shows negative loosening resistance because the sticking area on the contact surfaces is limited to two corner edges of the SW and the rotational force around these edges thus drastically leads to loosening. In regard to CSW, in the case of high axial force, it shows no apparent effect on preventing loosening. On the other hand, in the case of low axial force, it shows two opposite effects. The negative effect is an increase in the loosening rotation angle, while the positive one is the prevention of a decrease in axial force. When complete bearing-surface slip occurs, a CSW can prevent loosening because the positive effect becomes larger than the negative one. However, when only small bearing-surface slip occurs, a CSW cannot prevent loosening because the negative effect cancels the positive one.

scholarly journals Three-dimensional numerical investigations of new Austrian tunnelling method (NATM) twin tunnel interactions

2004 ◽  
Vol 41 (3) ◽  
pp. 523-539 ◽  
Author(s):  
C WW Ng ◽  
K M Lee ◽  
D KW Tang
Keyword(s):  
Axial Force ◽  
Load Transfer ◽  
Three Dimensional ◽  
Bending Moment ◽  
Vertical Movement ◽  
Maximum Settlement ◽  
Twin Tunnel ◽  
Horizontal Diameter ◽  
Natm Tunnel ◽  
The Right

A series of systematic, three-dimensional coupled finite element analyses was carried out to investigate the multiple interactions between large parallel hypothetical twin tunnels constructed in stiff clay using the new Austrian tunnelling method. Special attention was paid to the influence of lagging distance between the twin tunnel excavated faces (LT) and the load-transfer mechanism between the two tunnels. It is found that LT has a stronger influence on the horizontal movement than on the vertical movement of each tunnel, and it significantly affects the shortening of the horizontal diameter of the tunnels. The change of pillar width appears to be an approximately linear function of LT. The location of the maximum settlement is offset from the centerline of the pillar, and the offset increases with a range of LT values. The magnitude of the maximum settlement is independent of LT, however. As LT increases, there is a transfer of load from the lagging (right) tunnel to the leading (left) tunnel, resulting in an increase in the bending moment in the left tunnel but a decrease in the bending moment in the right tunnel. There is a corresponding increase in the axial force at the left springline of the left tunnel and a decrease in the axial force at the right springline of the right tunnel. Due to the twin tunnel interactions, the distributions of pore-water pressures are highly nonsymmetrical at both tunnels.Key words: NATM, tunnel, interaction, three-dimensional, numerical.

Numerical and Experimental Study of Axial Force and Hydraulic Performance in a Deep-Well Centrifugal Pump With Different Impeller Rear Shroud Radius

2013 ◽  
Vol 135 (10) ◽  
Author(s):  
Ling Zhou ◽  
Weidong Shi ◽  
Wei Li ◽  
Ramesh Agarwal
Keyword(s):  
Centrifugal Pump ◽  
Axial Force ◽  
Stokes Equations ◽  
Three Dimensional ◽  
Hydraulic Performance ◽  
Navier Stokes ◽  
Computational Domain ◽  
Pump Performance ◽  
Deep Well ◽  
Static Pressure Distribution

A multistage deep-well centrifugal pump (DCP) with different impeller rear shroud radius have been investigated both numerically and experimentally under multiconditons, which aims at studying the influence of impeller rear shroud radius to the axial force and pump hydraulic performance. During this study, a two-stage DCP equipped with three different impellers was simulated employing the commercial computational fluid dynamics (CFD) software ANYSY-Fluent to solve the Navier-Stokes equations for three-dimensional steady flow. High-quality structured grids were meshed on the whole computational domain. Test results were acquired by prototype experiments, and then compared with the predicted pump performance and axial force. The static pressure distribution in the pump passage obtained by numerical simulation was analyzed. The results indicated that the appropriate impeller rear shroud radius could improve the pump performance and lower the axial force significantly.

Simulation and Experimental Study on the Impact of Breadth of Back Blade on Axial Force Balance

2011 ◽  
Vol 130-134 ◽  
pp. 1568-1572
Author(s):  
Hui Wang ◽  
Jie Gang Mu ◽  
Miao Yin Su ◽  
Shui Hua Zheng ◽  
Jin Jing Zhao ◽  
...  
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Experimental Study ◽  
Axial Force ◽  
Three Dimensional ◽  
Force Balance ◽  
Simulation And Experiment ◽  
Simulation Results ◽  
The Impact ◽  
The Relationship

The paper studies the relationship between axial force and breadth of back blade by numerical simulation and experiment. On the basis of the RNG k-ε turbulence model and technology of compact local grids and regional computing, three dimensional numerical simulations to 100HZ165-250 centrifugal pump with various breadths were carried out. Through comparing and analyzing of the flow field, it can be seen that the axial force reduces with the increase of the back blade breadth. After that, the simulation results were verified by the experimental data got from different test devices, and it shows that the conclusions are reliable.

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